Base station antennas having an active antenna module and related devices and methods

ABSTRACT

Base station antennas include an externally accessible active antenna module releasably coupled to a recessed segment that is over a chamber in the base station antenna and that is longitudinally and laterally extending along and across a rear of a base station antenna housing. The base station antenna housing has a passive antenna assembly that cooperates with the active antenna module.

RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 17/209,562, filed Mar. 23, 2021, which claims priority to andthe benefit of U.S. Provisional Application Ser. No. 62/993,925, filedMar. 24, 2020, U.S. Provisional Application Ser. No. 63/075,344, filedSep. 8, 2020, U.S. Provisional Application Ser. No. 63/082,265, filedSep. 23, 2020, U.S. Provisional Application Ser. No. 63/124,442, filedDec. 11, 2020, and 63/136,757, filed Jan. 13, 2021, the contents ofwhich are hereby incorporated by reference as if recited in full herein.

BACKGROUND

The present invention generally relates to radio communications and,more particularly, to base station antennas for cellular communicationssystems.

Cellular communications systems are well known in the art. In a cellularcommunications system, a geographic area is divided into a series ofregions that are referred to as “cells” which are served by respectivebase stations. The base station may include one or more antennas thatare configured to provide two-way radio frequency (“RF”) communicationswith mobile subscribers that are within the cell served by the basestation. In many cases, each cell is divided into “sectors.” In onecommon configuration, a hexagonally shaped cell is divided into three120° sectors in the azimuth plane, and each sector is served by one ormore base station antennas that have an azimuth Half Power Beamwidth(HPBW) of approximately 65°. Typically, the base station antennas aremounted on a tower or other raised structure, with the radiationpatterns (also referred to herein as “antenna beams”) that are generatedby the base station antennas directed outwardly. Base station antennasare often implemented as linear or planar phased arrays of radiatingelements.

In order to accommodate the increasing volume of cellularcommunications, cellular operators have added cellular service in avariety of new frequency bands. While in some cases it is possible touse a single linear array of so-called “wide-band” radiating elements toprovide service in multiple frequency bands, in other cases it isnecessary to use different linear arrays (or planar arrays) of radiatingelements to support service in the different frequency bands.

As the number of frequency bands has proliferated, and increasedsectorization has become more common (e.g., dividing a cell into six,nine or even twelve sectors), the number of base station antennasdeployed at a typical base station has increased significantly. However,due to, for example, local zoning ordinances and/or weight and windloading constraints for the antenna towers, there is often a limit as tothe number of base station antennas that can be deployed at a given basestation. In order to increase capacity without further increasing thenumber of base station antennas, multi-band base station antennas havebeen introduced which include multiple linear arrays of radiatingelements. One common multi-band base station antenna design includes twolinear arrays of “low-band” radiating elements that are used to provideservice in some or all of the 617-960 MHz frequency band and two lineararrays of “mid-band” radiating elements that are used to provide servicein some or all of the 1427-2690 MHz frequency band. The four lineararrays are mounted in side-by-side fashion. There is also interest indeploying base station antennas that include one or more linear arraysof “high-band” radiating elements that operate in higher frequencybands, such as some, or all, of the 3.3-4.2 GHz frequency band.

FIGS. 1 and 2 illustrate examples of prior art base station antennas 10.The base station antenna 10 is typically mounted with the longitudinalaxis L of the antenna. 10 extending along a vertical axis (e.g., thelongitudinal axis L may be generally perpendicular to a plane defined bythe horizon) when the antenna 10 is mounted for normal operation. Thefront surface of the antenna 10 is mounted opposite the tower or othermounting structure, pointing toward the coverage area for the antenna10. The antenna 10 includes a radome 11 and a top end cap 20. The radome11 and the top end cap 20 can be a single integral unit, which may behelpful for waterproofing the antenna 10. The antenna 10 also includes abottom end cap 30 which includes a plurality of connectors 40 mountedtherein. As shown, the radome 11, top cap 20 and bottom cap 30 define anexternal housing 10 h for the antenna 10. An antenna assembly iscontained within the housing 10 h.

FIG. 2 illustrates that the antenna 10 can include one or more radios 50that are mounted to the housing 10 h. Antennas having integrated radiosthat can adjust the amplitude and/or phase of the sub-components of anRF signal that are transmitted through individual radiating elements orsmall groups thereof are referred to as “active antennas.” Activeantennas can steer the generated antenna beams in different directionsby changing the amplitudes and/or phases of the sub-components of RFsignals that are transmitted through the antenna. As the radios 50 maygenerate significant amounts of heat, it may be appropriate to vent heatfrom the active antenna in order to prevent the radios 50 fromoverheating. Accordingly, each radio 50 can include a (die cast) heatsink 54 that is mounted on the rear surface of the radio 50. The heatsinks 54 are thermally conductive and include a plurality of fins 54 f.Heat generated in the radios 50 passes to the heat sink 54 and spreadsto the fins 54 f. As shown in FIG. 2 , the fins 54 f are external to theantenna housing 10 h. This allows the heat to pass from the fins 54 f tothe external environment. Further details of example conventionalantennas can be found in co-pending WO2019/236203 and WO2020/072880, thecontents of which are hereby incorporated by reference as if recited infull herein.

SUMMARY

Pursuant to embodiments of the present invention, base station antennasare provided with housings that enclose a passive antenna assembly andthat are configured to releasably couple to an active antenna modulethat is at least partially external to the housing of the base stationantenna.

Embodiments of the present invention include a base station antenna thatincludes: a passive antenna assembly having a housing and a firstreflector. The housing has a rear wall. The base station antenna alsoincludes a separate active antenna module with a second reflectorcoupleable to or coupled to the housing of the passive antenna assembly.In position, the second reflector resides adjacent or inside the rearwall of the housing.

The housing has a front that can define an external radome with aninternal chamber between the front and the rear wall. The rear wall canhave or define a recess. The second reflector can reside adjacent thefirst reflector inside the recess.

The housing can have a front that defines an external radome with aninternal chamber between the front and the rear wall. The rear wall canhave or defines a recess and the second reflector can reside adjacentthe first reflector inside the recess.

The first reflector can have an aperture and at least a portion of thesecond reflector can be positioned in the aperture of the firstreflector.

The first reflector can have a longitudinal and lateral extent anddefines a reflector wall with wall segments that at least partiallysurrounds the aperture thereof.

The wall segments of the reflector wall of the first reflector canentirely surround the aperture.

The first reflector can be capacitively coupled to the second reflector.

At least one of the first reflector or the second reflector can beprovided by a frequency selective surface and/or substrate that can beconfigured to allow RF energy to pass through at one or more definedfrequency range and that is configured to reflect RF energy at adifferent frequency band.

The first reflector can have the frequency selective surface and/orsubstrate and can be configured to reflect RF energy at a low band andpass RF energy at a higher band.

The frequency selective surface and/or substrate can reside in thehousing behind low band dipole radiating antenna elements.

The base station antenna can further include low band dipole antennawith feed stalks. The feed stalks and/or radiating elements of the lowband dipole antenna can project forward of the frequency selectivesubstrate.

The base station antenna can include a third reflector that is anextension of the first reflector or that is coupled to the firstreflector. The third reflector can extend in a longitudinal directionand has a lateral extent. The third reflector can reside in the housingand extend longitudinally a distance greater than the first reflector.

The frequency selective surface and/or substrate can be co-planar withthe third reflector.

The frequency selective surface and/or substrate can be parallel to thethird reflector and can reside closer to an external, front radome ofthe housing than the third reflector.

The first reflector can have a longitudinal and lateral extent. Thesecond reflector can have a longitudinal and lateral extent. Thelongitudinal extent of the second reflector can be less than thelongitudinal extent of the first reflector.

The aperture of the first reflector and the recess provided by or in therear wall of the housing can be aligned and each can have a rectangularperimeter.

Other embodiments of the present invention are directed to base stationantennas that have a base station antenna housing with a top, a bottom,a front, a rear and right and left side walls extending between the topand the bottom and joining the front and rear. The rear has a recessedsegment that extends longitudinally and laterally across the rear of thebase station housing. The base station antenna also has a passiveantenna assembly in the base station antenna housing and an activeantenna module that includes radio circuitry and a plurality ofradiating elements that resides in the recessed segment of the rear ofthe base station antenna housing.

The front and the right and left side walls form at least part of aradome and the active antenna module can be configured to sealablycouple to the recessed segment.

The base station antenna can further include a back plate with an openaperture. The open aperture can extend longitudinally and laterallyacross the rear of the base station antenna housing. The active antennamodule can be sealably attached to the back plate and the active antennamodule can cover the open aperture of the back plate.

The active antenna module and/or the back plate can have a sealextending about a perimeter portion thereof.

The right and left side walls can have a first height along the recessedsegment. The right and left side walls can have a second height that isgreater than the first height at a second segment longitudinally spacedapart from the recessed segment. A difference between the first andsecond heights can be in a range of 0.25 inches and 6 inches.

The recessed segment can extend a length that can be in a range of20%-60% of a length of the rear of the base station antenna housing andcan extend in a width direction, perpendicular to the length direction,that can be in a range of 30-110% of a width of the rear of the antennabase housing

The base station antenna can further include a seal cap sealably coupledto the left and right side walls and the rear of the housing.

The base station antenna can further include a reflector in the basestation antenna housing. At least a portion of the reflector can resideforward of the back plate.

The reflector can have an open aperture that, with the base stationantenna in operative position, resides forwardly of the open aperture ofthe back plate.

The recessed segment can reside adjacent the top of the base stationantenna housing and terminate above a medial segment of the rear of thebase station antenna housing.

The back plate can be rectangular and can have a rectangular perimeterthat surrounds the open aperture and can be sealably coupled to theactive antenna module.

The base station antenna can further include first and second rails thatare laterally spaced and that longitudinally extend inside the basestation antenna.

The first and second rails can be coupled to the radome.

The base station antenna can further include first and secondcross-members coupled to the first and second rails that, together withthe first and second rails, surround a window configured to receive theactive antenna module.

The first and second rails can be sealably coupled to the radome and/orsealably coupled to the active antenna module.

The first and second rails can be coupled to the reflector.

The reflector can be positioned a distance in a range of 0.5 inches to 4inches from a back plate, or from the front, in a front to backdirection between the front and rear of the base station antennahousing.

Other aspects are directed to base station antennas that include: a basestation antenna housing having a top, a bottom, a front, a rear andright and left sides joining the front and rear. The rear has alongitudinally and laterally extending recessed segment or chamber. Thebase station antenna also includes a passive antenna assembly in thebase station antenna housing and an active antenna module sealablycoupled to the rear of the base station housing and extends over therecessed segment or chamber.

The active antenna module can have radio circuitry and a plurality ofradiating elements.

The base station antenna can further include a back plate with an openaperture. The open aperture can extend longitudinally and laterallyacross the rear of the base station housing over the open chamber. Theactive antenna module can be sealably attached to the back plate.

The active antenna module and/or the back plate can have a sealextending about a perimeter portion thereof.

The right and left side walls can have a first height along a recessedsegment of the rear. The right and left side walls can have a secondheight that is greater than the first height at a second segment of therear that is longitudinally spaced apart from the recessed segment. Adifference between the first and second heights can be in a range of0.25 inches and 6 inches.

The recessed segment can extend a length that is in a range of 20%-60%of a length of the rear of the base station antenna housing and canextend in a width direction, perpendicular to the length direction, thatcan be in a range of 30-110% of a width of the rear of the base stationantenna housing.

The base station antenna can further include a seal cap that can besealably coupled to the left and right side walls and the rear of thebase station antenna housing.

The base station antenna can further include a reflector in the basestation antenna housing. At least a portion of the reflector can resideforward of the back plate.

The recessed segment can reside adjacent the top of the base stationantenna housing and can terminate above a medial segment of the rear ofthe base station antenna housing.

The back plate can be rectangular and can have a rectangular perimeterthat surrounds the open aperture and can be sealably coupled to theactive antenna module.

The base station antenna can further have first and second rails thatare laterally spaced and that longitudinally extend inside the basestation antenna. The first and second rails can be coupled to the radomeand/or are sealably coupled to the active antenna module.

The base station antenna can further include first and second rails thatare laterally spaced and that longitudinally extend inside the basestation antenna; and first and second cross members that attach to thefirst and second rails. The first and second cross members and the firstand second rails can cooperate to form a window that receives an innerfacing portion of the active antenna module.

The first and second rails and the first and second cross members can besealably coupled to the active antenna module.

The first and second rails can be coupled to the reflector viarespective U-shaped connectors.

The reflector can be positioned a distance in a range of about 0.5 toabout 4 inches from a back plate in a front to back direction betweenthe front and rear of the base station antenna housing or from the frontof the housing that same distance where a back plate is not used. Theback plate can be sealably coupled to the active antenna module.

Still other aspects of the present invention are directed to activeantenna modules. The active antenna modules include a remote radio unit,an integrated filter and calibration board assembly coupled to theremote radio unit, an antenna assembly coupled to the remote radio unit,and a radome coupled to the antenna assembly with the antenna assemblysandwiched between the radome and the integrated filter and calibrationboard assembly.

The active antenna module can have a seal interface extending about aperimeter of the radome that is configured to sealably couple the activeantenna module to a base station antenna.

The radome can be a first radome and the active antenna module canfurther include a second radome that is coupled to and covers the firstradome.

Still other aspects of the present invention are directed to methods ofassembling a base station antenna. The methods include: mounting a basestation antenna housing to a mounting structure; aligning an activeantenna module with a recessed rear segment and/or chamber along a rearof the base station antenna housing before or after mounting the basestation antenna housing; then attaching the active antenna moduleagainst the base station antenna housing to couple the active antennamodule to the base station antenna housing.

Embodiments of the present invention provide antenna housings that havea back plate that resides adjacent a reflector and that also have apassive antenna assembly. The back plate can have a perimeter thatoptionally surrounds an aperture and that sealably engages an activeantenna module.

Embodiments of the present invention provide a base station antennahousing with a passive antenna assembly, a top cap, a bottom cap withconnectors and a radome extending between the top and bottom end caps.The radome has a front and a rear. The rear can have an externalrecessed segment that receives an active antenna module.

The antenna housing can have a seal cap that extends across a width ofthe radome and can be coupled to the rear of the antenna housing.

Embodiments of the present invention provide at least one active antennamodule that sealably couples to a rear of the base station antennahousing. The base station antenna housing encloses a passive antennaassembly. When assembled and/or in operation, the at least one activeantenna module is externally accessible thereby allowing for ease ofassembly, installation and/or replacement.

Embodiments of the present invention provide base station housings thatenclose a passive antenna and that sealably couple to an externallyaccessible active antenna module thereby allowing user selectable activeantenna modules (typically having respective antenna(s), filter(s) andradio(s)) to be coupled to a respective base station antenna housing.

Embodiments of the present invention provide a base station antenna thathas a base station antenna housing with a top, a bottom, a front, arear, and right and left sides joining the front and rear; a passiveantenna assembly in the base station antenna housing; and an activeantenna module slidably mountable to the base station antenna housingthrough the top of the base station antenna housing.

In position, the active antenna module can be sealably coupled to a topportion of the rear of the base station housing.

In position, the active antenna module can reside over and closes anopen chamber provided by the base station antenna housing.

The active antenna module can include a radome that resides in the openchamber and that faces an external radome of the front of the basestation antenna housing.

The rear of the base station antenna housing can have a longitudinallyand laterally extending open chamber that receives a radome of theactive antenna module.

The active antenna module can have an inwardly projecting top memberthat extends inwardly further than the radome of the active antennamodule.

The active antenna module can have rail couplers that slidably couple torails of the base station antenna housing.

The base station antenna housing can have outwardly projecting sidemembers that can extend for a sub-length of the base station antennahousing at a top portion of the base station antenna housing and thatcan couple to mounting hardware configured to mount the base stationantenna to a mounting structure.

The active antenna module can be coupled to the base station antennahousing and can be devoid of mounting hardware that mounts to themounting structure.

The active antenna module can have mounting hardware on a rear surfacethereof that is configured to attach to a mounting structure.

Yet other embodiments are directed to a base station antenna thatincludes at least one radome with one or more segments thereofinterposed between first and second reflectors.

The at least one radome can include first and second radomes withsegments thereof positioned between coupling surfaces of the first andsecond reflectors.

The first and/or second reflector can have a frequency selectivesurface/substrate.

The first and second reflector can be capacitively coupled.

Still other aspects are directed to a base station antenna that includesa base station antenna housing with a fixed reflector and a removablereflector that is configured to couple with the fixed reflector tothereby provide a common electrical ground.

The removable reflector can be capacitively coupled to the fixedreflector.

The removable reflector can be provided in an active antenna module thatis removably attached to the base station antenna housing.

Other embodiments are directed to a base station antenna that includes apassive antenna assembly having a housing and a first reflector and aseparate active antenna module having a second reflector coupleable toor coupled to the housing of the passive antenna assembly.

The housing can have a rear wall and, in position, the second reflectorcan reside inside the aperture of the rear wall of the housing.

The housing can have a front that defines an external radome with aninternal chamber between the front and the rear wall. The secondreflector can reside adjacent the first reflector inside the housing.

The first reflector can have an aperture and at least a portion of thesecond reflector can be positioned in the aperture of the firstreflector.

The first reflector has a longitudinal and lateral extent and can definea reflector wall with wall segments that at least partially surroundsthe aperture thereof.

The wall segments of the reflector wall of the first reflector canentirely surround the aperture.

The first reflector can be capacitively coupled to the second reflector.

At least one of the first reflector or the second reflector can beprovided by a frequency selective substrate that is configured to allowRF energy to pass through at one or more defined frequency range andthat is configured to reflect RF energy at a different frequency band.

The first reflector can be configured with a frequency selectivesubstrate and can be configured to reflect RF energy at a low band andpass RF energy at a higher band.

The frequency selective substrate can reside in the housing behind(feed) stalks of low band dipole antenna elements.

The base station can include low band dipole antenna with feed stalks,the feed stalks can project forward of a frequency selective surfaceand/or substrate, optionally the frequency selective substrate has openspaces that extend (adjacently) about the feed stalks.

Yet other embodiments are directed to a base station antenna thatextends along a longitudinal direction. The base station antennaincludes a plurality of columns of first radiating elements configuredfor operating in a first operational frequency band, each column offirst radiating elements comprising a plurality of first radiatingelements arranged in the longitudinal direction. The base stationantenna also includes a reflector positioned behind the plurality ofcolumns of first radiating elements and extending in the longitudinaldirection. The reflector has a frequency selective surface(s) and isconfigured such that electromagnetic waves within the first operationalfrequency band are substantially blocked by the reflector.

The frequency selective surface can be configured to reflect theelectromagnetic waves within the first operational frequency band.

The base station antenna can include a plurality of columns of secondradiating elements configured for operating in a second operationalfrequency band that is different from and does not overlap with thefirst operational frequency band. Each column of second radiatingelements can have a plurality of second radiating elements arranged inthe longitudinal direction. The frequency selective surface(s) isfurther configured such that electromagnetic waves within the secondoperational frequency band can propagate through the reflector.

The second operational frequency band can be higher than the firstoperational frequency band.

The reflector can provide the frequency selective surface(s) on aprinted circuit board.

The reflector can include a dielectric board having opposite first andsecond sides, the first and second sides facing respective columns ofthe first radiating elements, each can be formed with a periodicconductive structure, the periodic conductive structures forming thefrequency selective surface.

The periodic conductive structure on the first side of the dielectricboard can have a first array structure and the periodic conductivestructure on the second side of the dielectric board can have a secondarray structure that has a different pattern than the first arraystructure.

The frequency selective surface(s) can have a periodic conductivestructure a repeating pattern of polygonal shapes of metal elements.

The periodic conductive structures on the first and second sides of thedielectric board can be formed of metal.

The frequency selective surface(s) of the reflector can be provided by amulti-layer printed circuit board.

The reflector can be implemented as a multi-layer printed circuit board,one or more layers of which can be formed with a frequency selectivesurface configured such that electromagnetic waves within apredetermined frequency range can propagate through the reflector. Acombination of predetermined frequency ranges associated with the one ormore layers of the multi-layer printed circuit board can reflectelectromagnetic waves in the first operational frequency band.

The reflector can be a first reflector that is provided by a passiveantenna housing. The first radiating elements can be low band radiatingelements. The base station antenna can also include a second reflectorthat resides behind the first reflector.

The base station antenna can include at least one radome that residesbetween the first and second reflectors.

The at least one radome that resides between the first and secondreflectors can include first and second radomes stacked and spaced apartin a front to back direction behind a front surface of a housing of thebase station antenna. The front surface of the housing can define anexternal radome.

The second reflector can be provided by an active antenna module thatdetachably couples to the base station antenna.

The second reflector can reside behind a plurality of columns of secondradiating elements, each column of second radiating elements can includea plurality of second radiating elements arranged in the longitudinaldirection that operate in a second operational frequency band that ishigher than the first operational frequency band. Electromagnetic waveswithin the second operational frequency band can pass through the firstreflector.

The reflector can have a vertically extending primary surface thatresides between an internal radome and an external radome defined by afront of the base station antenna.

The base station antenna can have feed boards on right and left sides ofthe base station antenna that are perpendicular to a primary surface ofthe reflector.

The reflector can be attached to an internal radome.

The reflector can be provided by a flexible substrate.

The reflector can be malleable and/or flexible to have differentconfigurations, a pre-installation configuration and a fully installedconfiguration. The fully installed configuration can be a configurationthat conforms to a primary surface of an internal radome.

The internal radome is a first radome, the active antenna module canhave a second radome that is coupled to and extends across and along atleast part of the first radome.

Yet other embodiments are directed to a base station antenna thatincludes: a first reflector and a second reflector. The first and secondreflectors are capacitively coupled with at least one radometherebetween.

The at least one radome can define a dielectric.

The at least one radome can have a forwardmost surface that merges intoside portions that extend rearwardly. The side portions can havelaterally extending outer edge portions. The laterally extending outeredge portions can reside between the first and second reflectors.

The second reflector can have a forward primary surface that is forwardof a primary surface of the first reflector.

The at least one radome can include a radome provided by a detachableactive antenna module that provides the second reflector.

The first reflector can be a passive antenna assembly reflector. Aplurality of linear arrays of radiating antenna elements can resideforward of the second reflector.

The base station antenna can further include at least one feed boardthat is orthogonal to a primary surface of the first and/or secondreflector and positioned adjacent a right and/or left side of the basestation antenna.

The base station antenna can further include at least one radiatingelement that is coupled to the at least one feed board. The at least oneradiating element can extend forward of the first and/or secondreflector.

Yet other embodiments are directed to a base station antenna thatincludes a reflector having an opening extending longitudinally andlaterally between spaced apart left and right side portions of thereflector and a removable reflector portion having a length and widththat are +/−20% of a length and width of the opening and extends acrossand along the opening.

The reflector and/or the removable reflector portion can have afrequency selective surface.

The base station antenna can further include a pair of longitudinallyextending rails. The removable reflector portion can be coupled to therails.

The right and left side portions can have a width that is less than 50%of the width of the opening in a width direction of the base stationantenna.

At least one row of radiating antenna elements can extend along theright side portion and/or the left side portion of the reflector.

One or more radiating elements of the at least one row of radiatingelements can extend laterally across at least a portion of the right orleft side of the reflector and an adjacent portion of the removablereflector.

Yet other embodiments are directed to a base station antenna thatincludes a first housing member defining a front half of a housing ofthe base station antenna and a second housing member defining a backhalf of the housing of the base station antenna. The first and secondhousing members extend laterally and longitudinally and are sealedtogether.

The first housing member can have a front surface that merges into rightand left side portions that extend rearward. The second housing membercan have a rear surface that merges into right and left side portionsthat extend forward. The right and left side portions of the firsthousing member can be coupled to the right and left side portions of thesecond housing member along a joint interface that extendslongitudinally a length of the housing.

The second housing member can provide at least one laterally andlongitudinally extending recess adjacent a lower or upper end of thehousing. The recess can extend along a sub-length of the housing. Therecess can have a lateral extent that is 60-99% of a lateral extent ofthe housing.

The second housing member can have at least one external stepped regionthat rises above the recess and extends laterally and longitudinallyabout another sub-length of the housing

The base station antenna can further include a support member thatresides between the first and second housing members about a top and/orbottom end portion of the housing.

The support member can have a front that faces the first housing memberand a back that an inner surface of the second housing member. The backcan have a laterally extending medial segment that is recessed relativeto right and left sides of the support member. The right and left sidesof the support member can extend between the right and left sides of thefirst and second housing members.

Yet other embodiments are directed to a base station antenna thatincludes: a housing; at least one internal rail coupled to the housingthat extends longitudinally and has a first length; and at least oneexternal rail that extends longitudinally and that optionally has asecond length that is less than the first length. One or more of the atleast one internal rail is coupled to one or more of the at least oneexternal rail.

The at least one internal rail can have a right side internal rail and aleft side internal rail that are laterally spaced apart. The at leastone external rail can have a right side second external rail and a leftside external rail that are laterally spaced apart across a recessedportion of a rear of the housing.

A first one of the at least one internal rail can be sealably attachedto a first one of the at least one external rail to thereby inhibitwater flow into the housing.

The base station antenna can further include a bolt that extends througha first one of the at least one internal rail, a rear wall of thehousing and a first one of the at least one external rail.

The base station antenna can further include a spacer with a firstportion comprising a bolt hole surrounded by a second portion of adifferent material. The first portion of the spacer can reside in a holein a rear wall of the housing that has an opening with a shape thatcorresponds to the first portion of the spacer. The bolt can extendthrough the external rail, through the bolt hole of the spacer and intothe internal rail.

The first portion of the spacer can have increased rigidity relative tothe second portion. The second portion can be formed of a resilient,compressible seal material.

The spacer can have an elongate shape such that it has a length that isgreater than a width thereof

The second portion can reside against an outer surface of the rear wallof the housing, abutting an inner facing wall of the external rail,while the first portion of the spacer resides in the hole in the rearwall of the housing

The external rail can have a groove surrounding a bolt channel and aresilient seal member in the groove. The bolt can extend through thebolt channel with a head of the bolt and/or a collar extending forwardof the head of the bolt configured to compress the resilient seal memberthereby sealing the external rail against the rear wall of the housing.

The bolt comprises a resilient member extending in front of a bolt head.The resilient member can reside against a surface of the external railabout a bolt opening in the external rail.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art base station antenna.

FIG. 2 is a back view of another prior art base station antenna.

FIG. 3A is a partially exploded, side perspective view of a base stationantenna according to embodiments of the present invention.

FIG. 3B is an assembled, side perspective view of the base stationantenna shown in FIG. 3A.

FIG. 4 is a rear, side perspective view, of a base station antennahousing according to embodiments of the present invention.

FIG. 5 is a schematic partially exploded view of the base stationantenna housing shown in FIG. 4 .

FIG. 6A is a partial schematic illustration of a back plate andreflector for the base station antenna housing according to embodimentsof the present invention.

FIG. 6B is a rear perspective view of another embodiment of a basestation antenna according to embodiments of the present invention.

FIG. 7 is an enlarged schematic section view of a base station antennahousing with a passive antenna assembly therein that includes areflector according to embodiments of the present invention.

FIG. 8A is an enlarged schematic section view of a base station antennawith another embodiment of an internal rail configuration according toembodiments of the present invention.

FIG. 8B is a partial rear view of the base station antenna shown in FIG.8A.

FIG. 8C is a rear view of a portion of a base station antenna showingthe internal rails of FIG. 8A according to embodiments of the presentinvention.

FIG. 8D is rear view of the portion of the base station antenna housingshown in FIG. 8C with additional components added that form a back plateassembly according to embodiments of the present invention.

FIG. 8E is a greatly enlarged view of the back plate assembly shown inFIG. 8D.

FIG. 8F is a rear view of the base station antenna show in in FIGS. 8Aand 8B without the active antenna module coupled thereto according toembodiments of the present invention.

FIG. 9A is an example front, side perspective view of a base stationantenna, shown with the radome omitted, according to embodiments of thepresent invention.

FIG. 9B is an example rear, side perspective view of a base stationantenna, shown with the radome omitted, according to embodiments of thepresent invention,

FIG. 9C is a partial side, front perspective view of an example front ofan active antenna module shown inserted into the base station antennahousing according to embodiments of the present invention.

FIG. 9D is an enlarged partial front perspective view of the activeantenna module in the base station antenna housing according toembodiments of the present invention.

FIG. 9E is a partial section view of a base station antenna showingcooperating reflectors according to embodiments of the presentinvention,

FIG. 9F is an enlarged simplified, front partial section view of oneside of a base station antenna with first and second reflectorsseparated by a radome according to embodiments of the present invention.

FIG. 9G is an enlarged simplified, side perspective partial section viewof a base station antenna according to embodiments of the presentinvention.

FIGS. 9H-9O are greatly enlarged views of the interface of tworeflectors such as shown in one or more of FIG. 9E, 9F or 9Gillustrating coupling interfaces according to embodiments of the presentinvention.

FIG. 10A is a rear, side perspective view of an example active antennamodule aligned with a base station antenna housing for installationtherewith according to embodiments of the present invention,

FIG. 10B is a rear, side perspective view of the active antenna moduleshown in FIG. 10A installed to the base station antenna housing.

FIGS. 11A-11D illustrate a series of actions that can be used to installan active antenna module to a target base station antenna housing andmounted to mounting structure according to embodiments of the presentinvention.

FIG. 12A is a rear, side perspective view of another embodiment of anactive antenna module according to embodiments of the present invention.

FIG. 12B is an exploded view of the active antenna module shown in FIG.12A.

FIG. 13 is a rear, side perspective view of another embodiment of a basestation antenna according to embodiments of the present invention,

FIG. 14 is a rear, side perspective view of yet another embodiment of abase station antenna and corresponding active antenna module accordingto embodiments of the present invention.

FIG. 15 is an example flow chart of actions that can be used to assemblea base station antenna according to embodiments of the presentinvention.

FIG. 16A is a rear, side perspective view of another embodiment of abase station antenna and corresponding active antenna module, shownaligned for assembly, according to embodiments of the present invention.

FIG. 16B is a rear, side perspective assembled view of the embodimentshown in FIG. 16A.

FIG. 17A is a rear, side perspective view of the base station antennashown in FIG. 16A illustrating an example mounting hardwareconfiguration for a mounting structure and with the active antennamodule aligned for assembly according to embodiments of the presentinvention.

FIG. 17B is a rear, side perspective assembled view of the base stationantenna shown in FIG. 17A.

FIG. 18 is a rear, side perspective view of another embodiment of thebase station antenna of FIG. 16A showing an alternative hardwareconfiguration for mounting the base station antenna to a mountingstructure according to embodiments of the present invention.

FIG. 19A is a rear side perspective view of another embodiment of a basestation antenna housing and active antenna unit according to embodimentsof the present invention.

FIG. 19B is an assembled view of the device shown in FIG. 19A.

FIG. 20A is a front perspective view of an example frequency selectivesurface and/or substrate providing a reflector of the passive antenna ofthe base station antenna according to embodiments of the presentinvention.

FIG. 20B is a top perspective view of a portion of the frequencyselective surface and/or substrate shown in FIG. 20A also illustrating areflector of the active antenna module and example antenna elementbetween the two reflectors according to embodiments of the presentinvention.

FIG. 20C is a greatly enlarged front view of an example patch element ofa frequency selective surface and/or substrate according to embodimentsof the present invention.

FIG. 20D is a greatly enlarged side perspective view of a portion of anexample frequency selective surface and/or substrate (FSS) forming atleast part of a reflector for a base station antenna according toembodiments of the present invention.

FIG. 21A is a front perspective view of another embodiment of afrequency selective substrate/surface providing a reflector of the basestation antenna according to embodiments of the present invention.

FIG. 21B is a top perspective view of a portion of the frequencyselective substrate/surface shown in FIG. 21A also illustrating areflector of the active antenna module and example antenna elementbetween the two reflectors according to embodiments of the presentinvention.

FIG. 21C is a schematic, partial side view of an example FSS provided bya multi-layer substrate comprising a dielectric board and/or printedcircuit board according to embodiments of the present invention.

FIG. 21D illustrates an example FSS comprising top and bottom primarysurfaces of aligned cooperating patch elements according to embodimentsof the present invention.

FIG. 22A is a rear side perspective view of another embodiment of a basestation antenna housing, illustrating the frequency selectivesubstrate/surface at a different depth dimension, and an active antennaunit according to embodiments of the present invention.

FIG. 22B is an assembled view of the device shown in FIG. 22A.

FIG. 22C is a front, side perspective view of a portion of a basestation antenna comprising a frequency selective substrate/surfaceaccording to embodiments of the present invention.

FIG. 22D is an enlarged, front, side perspective view of a portion ofthe device shown in FIG. 22C.

FIG. 22E is an enlarged top, side perspective view of the device shownin FIG. 22C.

FIG. 22F is a front view of a portion of the base station antenna shownin FIG. 22C.

FIG. 22G is a front view of the frequency selective substrate/surfaceshown in FIG. 22C according to embodiments of the present invention.

FIG. 22H is a front, side perspective view of a portion of a basestation antenna comprising a frequency selective substrate/surfaceaccording to embodiments of the present invention.

FIG. 22I is a front, side partial perspective view of another examplereflector comprising an FSS and full metal outer perimeter sidesaccording to embodiments of the present invention.

FIG. 22J is a front, side partial perspective view of a portion of abase station antenna comprising feed boards that are parallel to andadjacent sidewalls of the base station antenna according to embodimentsof the present invention.

FIG. 23A is a side perspective view of an example active antenna modulewith an example adapter member(s) according to embodiments of thepresent invention.

FIG. 23B is an enlarged side view of the adapter member shown in FIG.23A.

FIG. 23C is an enlarged lateral section view of a base station antennacomprising the active antenna unit shown in FIG. 23A according toembodiments of the present invention.

FIG. 24 is a greatly enlarged section view of a portion of the basestation antenna with the assembled active antenna shown in FIG. 23C.

FIG. 25A is a side perspective view of an example active antenna modulewith an example adapter member according to embodiments of the presentinvention.

FIG. 25B is an enlarged side view of the adapter member (withcalibration circuit board) shown in FIG. 25A.

FIG. 25C is an enlarged lateral section view of a base station antennacomprising the active antenna unit shown in FIG. 25A according toembodiments of the present invention.

FIG. 26 is a greatly enlarged section view of a portion of the basestation antenna with the assembled active antenna shown in FIG. 25C.

FIG. 27A is a lateral section view of a base station antenna comprisingan active antenna unit according to embodiments of the presentinvention.

FIG. 27B is a greatly enlarged section view of a portion of the basestation antenna with the assembled active antenna shown in FIG. 27A.

FIG. 28A is a lateral section view of a base station antenna comprisingan active antenna unit according to embodiments of the presentinvention.

FIG. 28B is an enlarged view of a portion of the section view shown inFIG. 28A.

FIG. 29 is a side perspective view of an active antenna module alignedfor installation to a base station antenna housing from a top endthereof according to embodiments of the present invention.

FIG. 30A is a top end perspective view of the passive antenna housingshown in FIG. 29 but without the external front radome.

FIG. 30B is a partial bottom perspective view of the passive antennahousing shown in FIG. 29 .

FIG. 31A is a side perspective view of an active antenna module alignedfor installation to a base station antenna housing according toembodiments of the present invention.

FIG. 31B is an enlarged top, side perspective view of a portion of thebase station antenna shown in FIG. 31A with the active antenna moduleassembled thereto.

FIGS. 32A and 32B are examples of fixed attachment configurations forthe assembled base station antenna shown in FIG. 31B.

FIGS. 33A-33C are enlarged bottom side perspective views of the activeantenna module and bottom support features according to embodiments ofthe present invention.

FIG. 34 is a side perspective view of a portion of a base stationantenna with an active antenna module for installation thereto accordingto embodiments of the present invention.

FIG. 35A is an enlarged view of the bottom end portion of the activeantenna module and base station housing interface shown in FIG. 34 .

FIG. 35B is an end side perspective view of the bottom portion of theadapter plate shown in FIG. 35A.

FIG. 35C is a section view of the bolt and sleeve sub-assembly shown inFIG. 35A.

FIG. 36 is a side perspective view of a portion of a base stationantenna with an active antenna module for installation thereto accordingto additional embodiments of the present invention.

FIG. 37A is an enlarged side perspective view of the bottom portion ofthe adapter plate shown in FIG. 36 .

FIG. 37B is an enlarged side perspective view of a bottom portion of theadapter plate shown in FIG. 37A.

FIG. 37C is an enlarged side perspective view of the stop block shown inFIG. 37A.

FIG. 38 is a side perspective view of a portion of a base stationantenna with an active antenna module for installation thereto accordingto additional embodiments of the present invention.

FIG. 39A is an enlarged side perspective view of a bottom portion of theadapter plate and stop block shown in FIG. 38 .

FIG. 39B is an enlarged side perspective, partially exploded, view ofthe stop block and rail frame of the passive antenna shown in FIG. 38 .

FIG. 39C is an enlarged side perspective view of the stop block shown inFIG. 39B.

FIG. 40A is an enlarged simplified section view of a portion of anoptimized rail assembly of a passive antenna with a cooperating adapterplate of an active antenna module according to embodiments of thepresent invention.

FIG. 40B is an enlarged partial section view of a rivet nut used tostrengthen the structure of the antenna rail assembly shown in FIG. 40Aaccording to embodiments of the present invention.

FIG. 41A is a side perspective view of a fixed tilt mountable basestation antenna configuration according to embodiments of the presentinvention.

FIG. 41B is a side perspective view of an adjustable tilt mountable basestation configuration according to embodiments of the present invention.

FIG. 41C is a side perspective view of another adjustable tilt mountablebase station configuration according to embodiments of the presentinvention.

FIG. 41D is a set of mounting hardware allowing for 0-10 degrees ofadjustable tilt according to embodiments of the present invention.

FIG. 41E is a set of mounting hardware allowing for 0-5 degrees ofadjustable tilt according to embodiments of the present invention.

FIG. 42 is a side perspective view of a portion of a base stationantenna with an active antenna module according to additionalembodiments of the present invention.

FIG. 43 is a side perspective view of the base station antenna with theactive antenna module for installation thereto shown in FIG. 42 .

FIGS. 44A and 44B are side perspective views of a top portion of theactive antenna module and base station antenna shown in FIGS. 42 and 43illustrating a top hook arrangement for facilitating attachment forfield installation.

FIG. 44C is a side perspective view of a top portion of the activeantenna module and base station antenna comprising a differentattachment configuration according to embodiments of the presentinvention.

FIGS. 45A and 45B are side perspective views of example attachmentfeatures for securing the active antenna module to the base stationantenna shown in FIG. 42 according to embodiments of the presentinvention.

FIG. 46A is a simplified section view of a portion of a base stationantenna according to embodiments of the present invention.

FIG. 46B is a simplified perspective view of the portion of the basestation antenna shown in FIG. 46A with the reflector provided as afrequency selective surface and/or substrate (“FSS”) according toembodiments of the present invention.

FIG. 46C is a simplified perspective view of the portion of the basestation antenna shown in FIG. 46A with the reflector provided as a metalreflector according to embodiments of the present invention

FIG. 47A is a graph of the azimuth pattern for an antenna beam generatedby one of the lower-band linear arrays included in the base stationantenna of FIG. 46B, as generated by a computational model.

FIG. 47B is a graph of the azimuth pattern for an antenna beam generatedby one of the lower-band linear arrays included in the base stationantenna of FIG. 46C, as generated by a computational model.

FIG. 47C is a graph of peak three-dimensional directivity comparing thereflectors shown in FIGS. 46B and 46C.

FIG. 47D is a polar active chart comparing performance of the reflectorsshown in FIGS. 46B and 46C, as generated by a computational model.

FIG. 48A is a graph of the azimuth half power beamwidth (deg) versusfrequency (MHz) for one of the low band arrays for antennas that use theFSS reflector shown in FIG. 46B and the metal (PEC) reflector shown inFIG. 46C, as generated by a computational model.

FIG. 48B is a graph of the azimuth 10 dB beamwidth (deg) versusfrequency (MHz) for one of the low band arrays for antennas that use theFSS reflector shown in FIG. 46B and the metal (PEC) reflector shown inFIG. 46C, as generated by a computational model.

FIG. 49A is a simplified section view of a portion of a base stationantenna according to embodiments of the present invention.

FIG. 49B is a simplified perspective view of the portion of the basestation antenna shown in FIG. 49A with the reflector provided as afrequency selective surface and/or substrate (“FSS”) according toembodiments of the present invention.

FIG. 50A is a simplified section view of a portion of a base stationantenna according to embodiments of the present invention.

FIG. 50B is a simplified perspective view of the portion of the basestation antenna shown in FIG. 50A with two internal radomes residingbetween an active antenna reflector (capacitively coupled to a metalpassive antenna reflector) and the external radome of the base stationantenna according to embodiments of the present invention.

FIG. 51 is a graph of the directivity (in dB) of the low-band arraysversus frequency (MHz) for the base station antennas shown in FIGS. 50Aand 50B according to embodiments of the present invention.

FIGS. 52A and 52C are active Smith charts of one of the lower-bandlinear arrays included in the base station antenna shown in FIG. 49B, asgenerated by a computational model.

FIGS. 52B and 52D are active Smith charts of one of the lower-bandlinear array s included in the base station antenna shown in FIG. 50B,as generated by a computational model.

FIG. 53A is a graph of the front-to-back ratio versus frequency (at 180deg, +/−30 deg) of the base station antenna shown in FIG. 49B, asgenerated by a computational model.

FIG. 53B is a graph of the front-to-back ratio versus frequency (at 180deg, +/−30 deg) of the base station antenna shown in FIG. 50B, asgenerated by a computational model.

FIG. 54A is a partially transparent, perspective, simplified sectionview of a portion of a base station antenna with an active antennamodule and spaces for one or more feed boards that extend adjacent apassive antenna reflector (in a front to back direction of the basestation antenna) according to embodiments of the present invention.

FIG. 54B is a side perspective, partial view of a portion of a basestation antenna according to embodiments of the present invention.

FIG. 54C is a schematic, side perspective partial view of a portion ofthe base station antenna shown in FIG. 54B.

FIG. 55A is a simplified section view of a portion base station antennawith a passive antenna reflector provided as an FSS reflector in frontof an active antenna module and with side feed board(s) extending behindand/or in front of a primary surface of the FSS reflector according toembodiments of the present invention.

FIG. 55B is a side perspective view of the device shown in FIG. 55A.

FIGS. 56A and 56B are graphs of the azimuth pattern (scan angles of 0deg, 48 deg, respectively) for an antenna beam generated by one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B, as generated by a computational model.

FIG. 56C is a graph return loss (dB) versus frequency (GHz) at 0 and 48degree scan angles for an antenna beam generated by one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B, as generated by a computational model.

FIG. 56D is a polar active (RL) chart of 0 and 48 degree scan angles ofone of the lower-band linear arrays included in the base station antennaof FIGS. 55A, 55B, as generated by a computational model.

FIG. 56E is a graph of gain (dB) versus frequency (GHz) at 0 and 48degree scan angles of one of the lower-band linear arrays included inthe base station antenna of FIGS. 55A, 55B, as generated by acomputational model.

FIGS. 57A and 57B are graphs of the azimuth pattern (scan angles of 0deg, 48 deg, respectively) for an antenna beam generated by one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B and taken at a different horizontal (in the orientation shownin FIG. 55A) cut position from that of FIGS. 56A and 56B, as generatedby a computational model.

FIG. 57C is a graph of return loss (dB) versus frequency (GHz) at 0 and48 degree scan angles for an antenna beam generated by one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B, taken at a different horizontal (in the orientation shown inFIG. 55A) cut position from that of FIG. 56C, as generated by acomputational model.

FIG. 57D is a polar active (RL) chart of 0 and 48 degree scan angles ofone of the lower-band linear arrays included in the base station antennaof FIGS. 55A, 55B taken at a different horizontal (in the orientationshown in FIG. 55A) cut position from that of FIG. 56D, as generated by acomputational model.

FIG. 57E is a graph of gain (dB) versus frequency (GHz) at 0 and 48degree scan angles for one of the lower-band linear arrays included inthe base station antenna of FIGS. 55A, 55B, taken at a differenthorizontal (in the orientation shown in FIG. 55A) cut position from thatof FIG. 56E, as generated by a computational model,

FIG. 58A is a simplified side perspective view of a portion of a basestation antenna (shown without the front (external) radome of the basestation antenna) with an active antenna module and a detachable guidemember according to yet other embodiments of the present invention.

FIG. 58B illustrates the assembly shown in FIG. 58A without the guidemember shown in FIG. 58A according to embodiments of the presentinvention.

FIG. 59A is a simplified section view of the assembly shown in FIG. 58A(shown in housing of the base station antenna) according to embodimentsof the present invention.

FIG. 59B is a simplified section view of the assembly shown in FIG. 58B(shown in housing of the base station antenna) with the detachable guidemember removed and the reflector in position adjacent and/or residing onthe active antenna reflector according to embodiments of the presentinvention.

FIG. 60A is a rear perspective view of a base station antenna housingwith external and internal cooperating rails and a recess or cavityconfigured to receive an active antenna module according to embodimentsof the present invention.

FIG. 60B is a rear, side perspective view of the base station antennahousing shown in FIG. 60A.

FIG. 60C is a rear, side perspective view of the base station antennahousing shown in FIG. 60B but illustrates with the rear wall of thehousing in phantom or removed.

FIG. 61 is an end view of the base station antenna housing shown in FIG.60A but with an example active antenna module coupled to the cavityaccording to embodiments of the present invention.

FIG. 62A is a rear, side perspective view of an example front and backcooperating housing configuration according to embodiments of thepresent invention.

FIG. 62B is a rear, side perspective view of the front housing shown inFIG. 62A.

FIG. 62C is a side perspective view of an example internal supportmember of the housing shown in FIG. 62A according to embodiments of thepresent invention.

FIGS. 63A-63E are rear, side perspective views of example base stationantenna configurations according to example embodiments of the presentinvention.

FIG. 64A is a rear, side perspective view of a base station antennahousing configured to receive two active antenna modules according toembodiments of the present invention.

FIG. 64B is a rear, side perspective view of the base station antennahousing shown in FIG. 64A with two active antenna modules coupledthereto according to embodiments of the present invention.

FIG. 65 is a rear, side perspective view of the base station antennahousing shown in FIG. 64A but shown with a removable external reflectorcoupled to the top portion of the base station antenna housing while anactive antenna module is held at the bottom portion according toembodiments of the present invention.

FIG. 66 is a rear, side perspective view of the base station antennahousing shown in FIG. 64A illustrating two removable external reflectorsaccording to embodiments of the present invention.

FIG. 67A is a schematic front view of a reflector with radiatingelements according to embodiments of the present invention.

FIG. 67B is a schematic front view of another reflector with a cutoutand radiating elements according to embodiments of the presentinvention.

FIG. 67C of the reflector shown in FIG. 67B and also illustrating aremovable reflector extending behind some of the radiating elementsaccording to embodiments of the present invention.

FIG. 68A is a lateral section view of a base station antenna with anactive antenna module and internal radome(s) according to embodiments ofthe present invention.

FIG. 68B is a lateral section view of a base station antenna with anactive antenna module and internal radome(s) with a reflector andradiating elements held forward of the internal radome(s) according toembodiments of the present invention.

FIG. 69 is an enlarged partial section view of a portion of the basestation antenna housing with an example external rail to internal railinterface according to embodiments of the present invention.

FIG. 70A is an enlarged, partial side perspective view of the interfaceshown in FIG. 70A illustrating an example spacer positioned at theinterface according to embodiments of the present invention.

FIG. 70B is an enlarged side perspective view of the spacer and externalwall of the housing configured to receive at least a portion of thespacer shown in FIG. 70A according to embodiments of the presentinvention.

FIG. 71A is an enlarged front partial view of a portion of the externalwall of the housing shown in FIG. 70A illustrating a differentconfiguration of the wall from that shown in FIG. 70B according toembodiments of the present invention.

FIG. 71B is an enlarged top view of a spacer configured to couple to theexternal wall configuration shown in FIG. 71A according to embodimentsof the present invention.

FIG. 72A is an enlarged partial view of the external rail shown in FIG.69 according to embodiments of the present invention.

FIG. 72B is an enlarged side perspective view of the portion of theexternal rail shown in FIG. 72A.

FIG. 72C is a front view of the portion of the external rail shown inFIGS. 72A and 72B illustrated with a bolt coupled thereto according toembodiments of the present invention.

FIG. 73 is an enlarged side perspective view of an example bolt assemblyfor coupling the external rail and internal rail according toembodiments of the present invention.

FIG. 74 is an enlarged view of the portion of the base station antennashown in FIG. 69 illustrated with a spacer and bolt assembly coupledthereto according to embodiments of the present invention.

DETAILED DESCRIPTION

FIGS. 3A and 3B illustrate a base station antenna 100 according tocertain embodiments of the present invention. In the description thatfollows, the base station antenna 100 will be described using terms thatassume that the base station antenna 100 is mounted for use on a tower,pole or other mounting structure 300 (FIGS. 11A-11D) with thelongitudinal axis L of the antenna 100 extending along a vertical axisand the front of the base station antenna 100 mounted opposite thetower, pole or other mounting structure pointing toward the targetcoverage area for the base station antenna 100 and the rear of the basestation antenna 100 facing the tower or other mounting structure. Itwill be appreciated that the base station antenna 100 may not always bemounted so that the longitudinal axis L thereof extends along a verticalaxis. For example, the base station antenna 100 may be tilted slightly(e.g. less than 10°) with respect to the vertical axis so that theresultant antenna beams formed by the base station antenna 100 each havea small mechanical downtilt.

Referring to FIGS. 3A and 3B, the base station antenna 100 includes ahousing 100 h with the front and rear 100 f, 100 r and a top end 120 anda bottom end 130. The bottom end 130 includes a plurality of connectors140 mounted thereto. In some embodiments, the rear 100 r can include alongitudinally and laterally extending recessed segment 108. Therecessed segment 108 can longitudinally extend a sub-length “D” of therear 100 r of the housing 100 h. The distance D (the overall length ofthe active module 110) can be in a range of about 25%-95% of an overalllength L of the (passive) antenna housing 100 h, typically in a range ofabout 25%-60%, more typically in a range of about 25-40%, such as, forexample, a range of about 18-48 inches, in some embodiments.

The base station antenna 100 can include at least one active antennamodule 110. The term “active antenna module” refers to a cellularcommunications unit comprising radio circuitry including a remote radiounit (RRU) and associated antenna elements that are capable ofelectronically adjusting the amplitude and/or phase of the subcomponentsof an RF signal that are output to different antenna elements or groupsthereof. The active antenna module 110 comprises the RRU and antennaelements (e.g., a massive MIMO array) but may include other componentssuch as filters, a, calibration network, antenna interface signal group(AISG) controller and the like. As will be discussed further below, theactive antenna module 110 can be provided as a single integrated unit orprovided as a plurality of stackable units, including, for example,first and second sub-units such as a radio sub-unit (box) with the radiocircuitry and an antenna sub-unit (box) with massivemulti-input-multi-output (mMIMO) antenna elements and the first andsecond sub-units stackably attach together in a front to back directionof the base station antenna 100, with the antenna unit closer to thefront (external radome) of the base station antenna 100 than the radiounit.

The active antenna module 110 can be sealably coupled to the housing 100h and, when installed, can form part of the rear 100 r of the antenna100. The active antenna module 110 can have an inner facing surface thathas a seal interface 112 i that is be sealably and releasably coupled tothe rear 100 r of the housing 100 h to provide a water-resistant orwater-tight coupling therebetween. The active antenna module 110 can bemounted to the recessed segment 108 of the antenna housing 100 h so thata rear face 110 r is externally accessible and exposed to environmentalconditions. The active antenna module 110 can have an inner facingsurface with an outer perimeter portion 110 p.

As will be discussed further below, the antenna housing 100 h caninclude a passive antenna assembly 190 comprising radiating elements.The term “passive antenna assembly” refers to an antenna assembly havingradiating elements. The passive antenna assembly can be held in the basestation antenna housing 100 h and the base station antenna housing 100 hcan be releasably coupled to one or more active antenna modules 100comprising radio circuitry that is/are separate from the antennaelements of the passive antenna assembly 190.

Different active antenna modules 110 may be configured to have differentradios, radiating elements or other components whereby the activeantenna modules 110 can be different for different cellular serviceproviders. The active antenna module 110 can be interchangeably replacedwith another active antenna module 110 from the original equipmentmanufacturer (OEM) or from the same cellular communications serviceprovider or from different cellular communications service providers.Thus, a plurality of different active antenna modules 110 that havedifferent configurations can be interchangeably coupled to the basestation antenna housing 100 h. The different active antenna modules 110can each have the same exterior (perimeter) footprint and connectors ormay have different exterior footprints and/or connectors. The differentactive antenna modules 110 can have different depth dimensions (front toback). A respective base station antenna 100 can, for example, acceptdifferent active antenna modules 110 from different service providers ata field installation and/or factory installation site using differentadapter members or other mounting configurations that allow theinterchangeable field installation/assembly. The base station antenna100/antenna housing 100 h can thereby allow different active antennamodules 110 to be interchangeably installed, upgraded, or replaced. Thebase station antenna 100 can concurrently hold first and second activeantenna units 110, one above the other (FIGS. 13, 63D, 64B, forexample).

The length D of the recessed segment 108 can substantially correspond toa length dimension La of the active antenna module 110 that couples tothe housing 100 h. The length dimension La of the active antenna module110 is in a direction that corresponds to the longitudinal axis andlength dimension of the base station antenna 100. The distance D istypically greater than and within a range of +10%-+30% of the length Laof the active antenna module 110 (i.e., the length D of recess 108 maybe 10-30% larger than the length La of the active antenna module 110).The active antenna module 110 can be configured to extend acrosssubstantially an entire width dimension W of the rear 100 r of theantenna housing 100 h and optionally may extend outside the widthdimension a distance. The active antenna module 110 can have a widththat is, for example, within about +/−20% of the width dimension W ofthe rear 100 r of the housing 100 h, and optionally can have a widththat fits within the footprint of the front 100 f and rear 100 r of thehousing 100 h.

In some embodiments, the length D of the recessed segment may be withina range of about 20%-60% of the length of the rear 100 r of the basestation antenna housing 100 h and may extend in a width direction,perpendicular to the length direction, in a range of about 30-110% of awidth of the rear of the base station antenna housing 100 h.

The base station antenna 100 can have an elongate structuralconfiguration with a length dimension that extends along thelongitudinal axis L and with a width dimension W that is perpendicularto the length dimension. The width dimension W is typically less thanthe length dimension L. In some embodiments, L is >2×W, typically in arange of 2×W-10×W, more typically in a range of 2×W and 5×W.

Still referring to FIGS. 3A and 3B, the rear 100 r of the antennahousing 100 h can have an outer facing external rear surface 100 s thatincludes the recessed segment 108. The recessed segment 108 can extendover a sub-length of the overall length L of the antenna housing 100 hand can merge into a second segment 151 that extends over a differentsub-length of the overall length L of the antenna housing 100 h. Thesecond segment 151 can terminate at the bottom 130. The recessed segment108 can reside closer to the top 120 than the second segment 151. Thesecond segment 151 can have a closed outer surface that is defined by aportion of the radome 150. The recessed segment 108 can have an openouter surface exposing a rear facing open chamber 155. The secondsegment 151 may optionally have a length (in a direction correspondingto the longitudinal axis L of the base station antenna 100) that is lessthan, the same as, or greater than that of the recessed segment 108.

As shown in FIGS. 3A and 3B, the active antenna module 110 can include aheat sink 115 with thermally conductive fins 115 f. The fins 115 f maybe arranged in a pattern of parallel angled fins. The fins 115 f may beconfigured as first and second sets of fins 115 f spaced apart across amedially located and longitudinally extending gap space 116. Some or allof the thermally conductive fins 115 f can be provided at an angle “P”in a range of 30-60 degrees from horizontal or an axis perpendicular tothe longitudinal axis L, in a use orientation, more typically at anangle from the axis perpendicular to the longitudinal axis that is about45%. Some fins 115 f can be longer than others, as shown. The activeantenna module 110 can include one or more finger grips 118, which areshown as laterally spaced apart pairs of finger grips 118, onepositioned on each side of the active antenna module 110 for ease ininstallation or removal. In other embodiments, finger grips 118 mayalternatively or additionally be located at the top and bottom of theactive antenna module 110 and/or at different locations about the activeantenna module 110.

Referring to FIGS. 3A, 3B, 4 and 5 , the base station antenna housing100 h can comprise a back plate 160 that includes an opening 163 (FIG. 5). A seal 112 can be provided between the back plate 160 and the innerfacing surface of the active antenna module 110. In some embodiments,the outer perimeter portion 110 p of the active antenna module 110 cancomprise a seal interface 112 i with the seal on an internal facingsurface that can be sealably coupled to the back plate 160. In someembodiments, the seal 112 can be provided on the back plate 160 or in ahousing interface 100 i.

One or both of a rear facing surface of the back plate 160 and the sealinterface 112 i of the inner facing surface of the active antenna module110 can comprise an O-ring, gasket or other seal 112 to sealably couplethe active antenna module 110 to the back plate 160 and therefore, thehousing 100 h.

The back plate 160 can have an outer perimeter portion 160 p thatexternally surrounds the active antenna module 110. The outer perimeterportion 160 p of the back plate 160 can have a lower end 161 thatsealably couples to a seal cap 165 and defines a seal interface 100 i tothe housing 100 h.

As shown in FIG. 5 , the housing 100 h can include a first side wall101, a front wall 102, and a second side wall 103 that cooperate todefine a chamber 155. The first side wall 101, the front wall 102 andthe second side wall 103 can be provided as a “u-shaped” unitary formedstructure defining part of the radome 150 with the closed end of the “u”being longer than the sides. In some embodiments, two or more of theside walls 101, 103 and front wall 101 can be separate walls attachedtogether at joints, although more typically they are formed as amonolithic structure.

Still referring to FIG. 5 , the side walls 101, 103 can have a firstrearwardly extending length “h₁” over a sub-length of the housing 100 hthat extends to the top 120 and a second greater rearwardly extendinglength h₂ over a different sub-length of the housing 100 h that extendsto the bottom 130, each rearwardly extending length h₁, h₂ can be lessthan a width dimension “W” of the front wall 102. The difference in therearwardly extending lengths h₂−h₁ can define a size of the step formingthe stepped recess 108 in the rear surface 100 s. In some embodiments,h₂−h₁ and/or the step measured from the rear surface height at therecess to the height adjacent maximal segment of the rear 100 r of thehousing 100 h can be in a range of 0.2 inches to 4 inches, moretypically in a range of about 0.5 inches to 2 inches.

The second segment 151 of the radome 150 at the rear 100 r of thehousing 100 h can extend from a first location adjacent the lower end161 of the back plate 160 to the bottom 130. The chamber 155 can extendan entire length of the housing 100 h, with an upper portion of thechamber 155 being forward of the back plate 160 and at least a portionof the active antenna module 110. The chamber 155 can hold the passiveantenna assembly 190 (FIG. 9 ).

The back plate 160 can reside behind a portion of a reflector 170 (FIG.5 ) of the passive antenna assembly 190. Referring to FIG. 7 , the backplate 160 can be a distance “d”, in a front to back direction of theantenna housing 100 h, from the reflector 170 of the passive antennaassembly 190. The distance “d” can be in a range of about 0.01 inches toabout 4 inches or in a range of about 0.5 and 4 inches, in someembodiments.

Referring to FIGS. 4 and 5 , in some embodiments, the outer perimeterportion 160 p of the back plate 160 can surround an aperture 163 thatextends through the back plate 160. The outer perimeter portion 160 pand aperture 163 can be polygonal, typically rectangular. A seal 112 canbe provided in either or both the outer facing surface of the back plate160 and/or the inner facing surface of the active antenna module 110 andthe seal 112 and seal interface 112 i can have a closed endlessconfiguration, such as a rectangular, oval or circular shape extendingabout the chamber 155. However, other shaped perimeters, seals andapertures may be used.

The aperture 163 of the back plate 160 can be aligned with an aperture173 formed in the reflector 170 of the passive antenna assembly 190. Theaperture 173 in the reflector 170 of the passive antenna assembly 190can also be polygonal, shown as rectangular. The aperture 173 of thereflector 170 of the passive antenna assembly 190 can have an area thatsubstantially corresponds to the area of the aperture 163 of the backplate 160, such as within about +/−20% of the area of the aperture 163,in some embodiments. The seal 112 can have a shape and size that extendsabout the aperture 163.

In some embodiments, the back plate 160 is not required and the activeantenna module 110 can sealably, and preferably releasably, coupled tothe housing 100 h in other manners, such as directly to a rear segmentof the housing 100 h (FIG. 6B) while providing a water-resistant orwater-tight coupling therebetween.

The back plate 160 may have a closed outer perimeter 160 p thatsurrounds the aperture 163 defining a frame configuration 164 thatsurrounds the aperture 163. In other embodiments, the back plate 160 mayterminate adjacent the second segment 151 of the radome 150, or theframe 164 or any side thereof is not required.

The reflector 170 of the passive antenna assembly 190 may have a closedouter perimeter 170 p with a reflector wall having side segments 170 sthat at least partially surround the aperture 173, optionally defining aframe configuration 174 that surrounds the aperture 173. In otherembodiments, the reflector 170 of the passive antenna assembly 190 mayterminate adjacent the second segment 151 of the radome 150, or theframe 174 and/or any side thereof is not required. In some embodiments,the reflector 170 can be provided as an extension of the main reflector214 (FIG. 9A) in the passive antenna assembly 190. In some embodiments,the reflector 170 can be separate from the main reflector 214 (FIG.19A). As will be discussed further below, the reflector 170 can compriseand/or be configured as a frequency selective substrate and/or surface170 f. Where separate, the reflector 170 may be electrically coupled tothe main reflector 214.

In some embodiments, as shown in FIG. 6A, the back plate 160 and/orreflector 170 can be replaced with a respective back plate 160′ and/orreflector 170′ that comprise a plurality of apertures 163, 173. As shownin FIG. 6B, the back plate 160 is not required and the active antennamodule 110 can directly couple to the housing at seal interfaces 100 i.Also, or alternatively, the reflector 170 can terminate adjacent the topend of the second segment 151 of the rear surface 100 s of the housing100 h.

The back plate 160 can reside inside the recessed segment 108 of therear 100 r of the housing 100 h and/or rear surface of the radome 150.The back plate 160 can be recessed relative to the top 120 of thehousing 100 h (FIG. 10A). The top 120 of the housing 100 h can beprovided as an end cap or formed by a folded extension of the front wall102. The bottom 130 is typically provided as an end cap having aplurality of connectors 140 mounted therein.

Referring to FIGS. 3A, 3B, 4 and 5 , a seal cap 165 can be coupled tothe rear 100 r of the housing 100 h and reside between the recessedsegment 108 and the second segment 151 of the radome 150. The seal cap165 can sealably engage longitudinally spaced apart housing interfaces100 i to enclose the internal chamber 155 (FIG. 5 ) thereunder createdby the configuration of the recessed segment 108 and the second segment151. The seal cap 165 can include a seal 165 s on an inner facing(outer) perimeter surface. For releasably coupled configurations, theseal 165 s can include one or more of a gasket, O-ring or grease. Inother embodiments, epoxy, adhesive or other seal attachmentconfigurations may be used.

Referring to FIGS. 4 and 5 , the seal cap 165 can have a base segment166 and a back segment 167 that extends rearwardly from the housing 100h a further distance than the base segment 166. The back segment 167 canreside at a rearwardly extending distance “h” that is greater than thebase segment 166 and that may be, for example, in a range of about 1.0inch and about 10 inches. The seal cap 165 can have a length “d” thatextends in the longitudinal direction that is between about 0.25-5inches, more typically in a range of about 0.5 inches and about 2inches.

Referring to FIG. 7 , the base station antenna 100 may have a generallyrectangular cross-section, e.g., a pair of long sides joined by a pairof short sides. The long sides correspond to the front 100 f and rear100 r of the antenna housing 100 h. The short sides correspond to theside walls 101, 103.

Referring to FIGS. 5 and 7 , the antenna housing 100 h can comprise atleast one internal rail 180. As shown, the at least one rail 180 can beprovided as first and second rails 180 ₁, 180 ₂ that are laterallyspaced apart across the width dimension of the base station antenna 100.The at least one rail 180 extends in the longitudinal direction betweenthe top 120 and bottom 130 of the antenna housing 100 h. The at leastone rail 180 can extend over the entire length L of the antenna housing100 h as shown in FIG. 5 or may extend over a sub-length.

In use or with the rear of the housing 100 h facing upward, the at leastone rail 180 can reside adjacent the back plate 160 and behind thereflector 170 in FIG. 5 . The at least one rail 180 can providestructural support, increased structural rigidity and/or structuralreinforcement to the antenna housing 100 h for facilitating properpositional tolerances of (e.g., blind mate) connectors and/or foraccommodating the weight of the externally accessible active antennamodule 110.

Referring to FIG. 7 , the at least one rail 180 can have a geometricallyshaped configuration that structurally and sealably couples to free endportions 101 e, 103 e of the side walls 101, 103 along the recessedsegment 108 of the antenna housing 100 h. The at least one rail 180 mayalso be mounted to the back plate 160.

The reflector 170 of the passive antenna assembly 190 can compriselaterally spaced apart mounting members 172. The mounting members 172can be U-shaped members with a first leg portion 172 l 1 and a secondleg portion 172 l ₂ separated by a center portion 172 c. Thisconfiguration may provide increased structural rigidity over a singleleg configuration. The first leg portion 172 l ₁ can be attached to thereflector 170 and the second leg portion 172 l ₂ can be attached to therail 180. The center portion 172 c can extend perpendicular to thereflector 170.

The free ends 101 e, 103 e of the side walls 101, 103 can terminate intorespective sets of laterally spaced apart fingers 101 f, 103 f of theradome 150. Each set of fingers 101 f, 103 f can sealably couple to arespective one the rails 180 ₁, 180 ₂.

The at least one rail 180 can comprise a rigid or semi-rigid substratematerial such as metal and can also include a seal material such as anelastomeric and/or polymeric material for facilitating a suitablewater-resistant seal with the radome 150. Sealant material can also oralternatively be provided with adapter plates and/or the active antennamodule 110.

In some embodiments, the reflector 170 can be part of the main reflector214 so that the reflector 170/214 extends substantially the entirelength of the antenna 100, with the upper portion having the aperture173. The at least one rail 180 can be a pair of rails 180 ₁, 180 ₂, onemounted on each side of the reflector 170/214 and together the reflector170/214 and rails 180 (and the back plate 160 which may reside only atthe top portion of the antenna 100) provide the structural integrity ofthe antenna 100. The internal components of the antenna 100 such as theantenna assembly 190 can be mounted directly or indirectly on thereflector 170/214. The radome 150 can be slid over all of these internalcomponents and the three caps 120, 130, 165 can then be placed on theradome 150. Also, the antenna 100 can include internal U-shaped brackets(not shown) that extend rearwardly from the reflector 170/214 in thelower part of the antenna that provide additional support such as tohelp rigidize the reflector 170/214. Other brackets can be provided formounting to a support structure such as a pole.

Referring to FIGS. 8A-8F, in some embodiments, the guide rails 180′ canbe configured to provide a direct contact interface to the activeantenna module 110 and no back plate is required. First and secondlongitudinally spaced apart and laterally extending cross-members 169can be coupled to the rails 180 ₁, 180 ₂ providing a window 188 over thecavity 155 provided by the side wall segments 101, 103 and front wallsegment 102 of the housing 100 h for receiving an inner facing portionof the active antenna module 110. The active antenna module 110 can besealably coupled to the cross members 169 and the rails 180 ₁, 180 ₂.

Referring to FIGS. 8B, 8E, the cross-members 169 can include spacedapart apertures 166 and the rails 180 ₁, 180 ₂ can include spaced apartapertures 183 to receive fixation members 19, such as screws, pins, orrods that attach (a front facing outer perimeter portion 110 p) theactive antenna module 110.

Referring to FIG. 8A, the rails 180 ₁, 180 ₂ can each have a firstplanar surface 180 p 1 that (sealably) attaches to a respectivecross-member 169, and a second planar surface 180 p 2 that resides in adifferent plane from the first planar surface and that (sealably)couples to the mating surface of the active antenna module 110. Thefirst planar surface 180 p 1 can have a larger lateral extent than thesecond planar surface 180 p 2 can reside closer to the center of thehousing 100 h than the second planar surface 180 p 2.

The reflector 170 can be indirectly or directly coupled to the side wallsegments 101, 103 shown as coupled via the rails 180′ in FIGS. 8A, 8C.

The at least one rail 180 can be provided as an integral formed rail inone or both of the side walls 101, 103. The side wall segments 101, 103comprise part of the radome 150 and can be formed of fiberglass, plasticor other appropriate materials.

In some embodiments, a sealant can be over molded to provide a sealmaterial 180 s (FIG. 8A) such as at planar segments 180 p 1, 180 p 2.The rails 180′ can be coupled to or formed (e.g., extruded) as part ofthe side wall segments 101, 103.

FIGS. 9A-9D and 12B illustrate an example active antenna module 110 ingreater detail. The active antenna module 110 includes radio circuitryand can be partially inserted through the rear of the housing 100 rand/or back plate 160. As shown best in FIG. 12B, the active antennamodule 110 can comprise an RRU (remote radio unit) unit 1120. The activeantenna module 110 can also include a heat sink 115 and fins 115 f. Theactive antenna module 110 can also include a filter and calibrationprinted circuit board assembly 1180, and an antenna assembly 1190comprising a reflector 1172 and radiating elements 1195. The antennaassembly 1180 may also include phase shifters 1191, which mayalternatively be part of the filter and calibration assembly 1180. Theradiating elements 1195 can be provided as a massive MIMO array. The RRUunit 1120 is a radio unit that typically includes radio circuitry thatconverts base station digital transmission to analog RF signals and viceversa. One or more of the radio unit or RRU unit 1120, the antennaassembly 1190 or the filter and calibration assembly 1180 can beprovided as separate sub-units that are attachable (stackable). The RRUunit 1120 and the antenna assembly 1190 can be provided as an integratedunit, optionally also including the calibration assembly 1180. Whereconfigured as sub-units, different sub-units can be provided by OEMs orcellular service providers while still using a common base stationantenna housing 100 h and passive antenna assembly 190 thereof. Theantenna assembly 1190 can couple to the filter and calibration boardassembly 1180 via, for example, pogo connectors 111. Other connectorconfigurations may be used for each of the connections, such as, forexample 3-piece SMP connectors. The RRU unit 1120 can also couple to thefilter and calibration board assembly 1180 via pogo connectors 111thereby providing an all blind-mate connection assembly withoutrequiring cable connections. Alignment of the cooperating componentswithin a tight tolerance may be needed to provide suitable performance.

The antenna module 110 may include all of the components of the activeantenna module 110′ shown in FIG. 12B except for the illustrated secondradome 1119. An antenna module 110′ further includes such a secondradome 1119. The second radome 1119 covers the first radome 119 foraesthetic purposes but is otherwise the same as the active antennamodule 110 discussed above. The second radome 1119 can be used as anaesthetic cover when the active antenna module 110 is provided forshipment as a standalone product. This is due to the first radome 119having a relatively unusual shape to fit into the window 188 and/or 173.The RRU unit 1120 can be wider than the antenna element array 1191, 1195so the radome 119 is shaped to allow the radiating elements 1195 (FIGS.9A, 12B) but not the radio 1120, or at least not the entire radio/radiounit 1120, to fit inside the housing 100 h. The radiating elements 1195(FIG. 12B) can extend through a back plate 160, a window 188 formed bythe rails 180′ and/or through the passive/primary reflector 214. In someembodiments, before/when the active antenna module 110 is integratedinto the passive antenna housing 100 h, the second radome or cover 1119can be removed to allow the antenna module 110′ to fit through theapertures/window 188, 173 in the antenna housing 100 h. The first radome119 remains intact on the active antenna module 110 as it can beconfigured to provide both the radome 119 of the active antenna module110 and provide part of the (sealable) coupling to the housing 100 h.

The RRU unit 1120 can have a rectangular body with an outer perimetercomprising a planar ledge 1121 that can define the seal interface 112 iand a plurality of spaced apart apertures 112 a that can receivefixation members 117 (FIG. 3B) to attach to the housing 110 h. Inparticular, screws or other fixation members 117 can be positioned aboutthe perimeter of the chamber 150 and extend through apertures 112 a in aperimeter 110 p of the active antenna module 110, 110′ to connect theactive antenna module 110, 110′ to the guide rails 180 and/or back plate160. Another connection configuration can use an adapter plate that canconnect the active antenna module 110 to the rails 180, 180′ in theantenna housing 100 h (not shown).

The active antenna module 110, 110′ can also include externallyaccessible connectors 113 on a bottom end thereof as shown in FIGS. 10A,and 12A for example. The externally accessible connectors 113 areexternally accessible in-use and when the active antenna module 110 iscoupled to the base station antenna housing 100 h. The externallyaccessible connectors 113 are typically for connecting power and fiberoptic cables to the active antenna module 110. In some embodiments, oneor more connectors 113 can be conjured to couple to an AISG cable tocontrol (passive) RET. Connectors can be provided at other locationssuch as sides or both ends and sides.

FIGS. 9A and 9B are a front view and a rear view, respectively, of thepassive antenna assembly 190 of base station antenna 100 (with theactive antenna module 110 mounted thereon). As shown, the antennaassembly 190 includes a main backplane 210 that has side walls 212 and amain reflector 214. The backplane 210 may serve as both a structuralcomponent for the antenna assembly 190 and as a ground plane andreflector for the radiating elements mounted thereon. The backplane 210may also include brackets or other support structures (not shown) thatextend between the side walls 212 along the rear of the backplane 210.Various mechanical and electronic components of the antenna 100 aremounted between the side walls 212 and the back side of the mainreflector 214, such as phase shifters, remote electronic tilt units,mechanical linkages, controllers, diplexers, and the like as is wellknown in the art.

The main backplane 210 defines a main module of the passive antennaassembly 190. The main reflector 214 may comprise a generally flatmetallic surface that extends in the longitudinal direction L of theantenna 100. The main reflector 214 can be the reflector 170 discussedabove or can be an extension of, coupled to or different from thereflector 170 discussed above. If the main reflector 214 is a separatereflector it is coupled to the reflector 170 to provide a commonelectrical ground.

Some of the radiating elements (discussed below) of the antenna 100 maybe mounted to extend forwardly from the main reflector 214, and, ifdipole-based radiating elements are used, the dipole radiators of theseradiating elements may be mounted approximately ¼ of a wavelength of theoperating frequency for each radiating element forwardly of the mainreflector 214. The main reflector 214 may serve as a reflector and as aground plane for the radiating elements of the antenna 100 that aremounted thereon.

Referring to FIG. 9A, the base station antenna 100 can include one ormore arrays 220 of low-band radiating elements 222, one or more arrays230 of first mid-band radiating elements 232, one or more arrays 240 ofsecond mid-band radiating elements 242 and one or more arrays 250 ofhigh-band radiating elements 1195. The radiating elements 222, 232, 242,1195 may each be dual-polarized radiating elements. Further details ofradiating elements can be found in co-pending WO2019/236203 andWO2020/072880, the contents of which are hereby incorporated byreference as if recited in full herein.

The low-band radiating elements 222 are mounted to extend forwardly fromthe main or primary reflector 214 (and/or the reflector 170) and can bemounted in two columns to form two linear arrays 220 of low-bandradiating elements 222. Each low-band linear array 220 may extend alongsubstantially the full length of the antenna 100 in some embodiments.

The low-band radiating elements 222 may be configured to transmit andreceive signals in a first frequency band. In some embodiments, thefirst frequency band may comprise the 617-960 MHz frequency range or aportion thereof (e.g., the 617-896 MHz frequency band, the 696-960 MHzfrequency band, etc.). The low-band linear arrays 220 may or may not beused to transmit and receive signals in the same portion of the firstfrequency band. For example, in one embodiment, the low-band radiatingelements 222 in a first linear array 220 may be used to transmit andreceive signals in the 700 MHz frequency band and the low-band radiatingelements 222 in a second linear array 220 may be used to transmit andreceive signals in the 800 MHz frequency band. In other embodiments, thelow-band radiating elements 222 in both the first and second lineararrays 220-1, 220-2 may be used to transmit and receive signals in the700 MHz (or 800 MHz) frequency band.

The first mid-band radiating elements 232 may likewise be mounted toextend upwardly from the main reflector 214 and may be mounted incolumns to form linear arrays 230 of first mid-band radiating elements232. The linear arrays 230 of mid-band radiating elements 232 may extendalong the respective side edges of the main reflector 214. The firstmid-band radiating elements 232 may be configured to transmit andreceive signals in a second frequency band. In some embodiments, thesecond frequency band may comprise the 1427-2690 MHz frequency range ora portion thereof (e.g., the 1710-2200 MHz frequency band, the 2300-2690MHz frequency band, etc.). In the depicted embodiment, the firstmid-band radiating elements 232 are configured to transmit and receivesignals in the lower portion of the second frequency band (e.g., some orall of the 1427-2200 MHz frequency band). The linear arrays 230 of firstmid-band radiating elements 232 may be configured to transmit andreceive signals in the same portion of the second frequency band or indifferent portions of the second frequency band.

The second mid-band radiating elements 242 can be mounted in columns inthe upper portion of antenna 100 to form linear arrays 240 of secondmid-band radiating elements 242. The second mid-band radiating elements242 may be configured to transmit and receive signals in the secondfrequency band. In the depicted embodiment, the second mid-bandradiating elements 242 are configured to transmit and receive signals inan upper portion of the second frequency band (e.g., some, or all, ofthe 2300-2700 MHz frequency band). In the depicted embodiment, thesecond mid-band radiating elements 242 may have a different design thanthe first mid-band radiating elements 232.

The high-band radiating elements 1195 can be mounted in columns in theupper medial or center portion of antenna 100 to form (e.g., four)linear arrays 250 of high-band radiating elements. The high-bandradiating elements 1195 may be configured to transmit and receivesignals in a third frequency band. In some embodiments, the thirdfrequency band may comprise the 3300-4200 MHz frequency range or aportion thereof.

In the depicted embodiment, the arrays 220 of low-band radiatingelements 222, the arrays 230 of first mid-band radiating elements 232,and the arrays 240 of second mid-band radiating elements 242 are allpart of the passive antenna assembly 190, while the arrays 250 ofhigh-band radiating elements 1195 are part of the active antenna module110. It will be appreciated that the types of arrays included in thepassive antenna assembly 190, and/or the active antenna module 110 maybe varied in other embodiments.

It will also be appreciated that the number of linear arrays oflow-band, mid-band and high-band radiating elements may be varied fromwhat is shown in the figures. For example, the number of linear arraysof each type of radiating elements may be varied from what is shown,some types of linear arrays may be omitted and/or other types of arraysmay be added, the number of radiating elements per array may be variedfrom what is shown, and/or the arrays may be arranged differently. Asone specific example, two linear arrays 240 of second mid-band radiatingelements 242 may be replaced with four linear arrays of ultra-high-bandradiating elements that transmit and receive signals in a 5 GHzfrequency band.

The low-band and mid-band radiating elements 222, 232, 242 may each bemounted to extend forwardly of and/or from the main reflector 214.

Each array 220 of low-band radiating elements 222 may be used to form apair of antenna beams, namely an antenna beam for each of the twopolarizations at which the dual-polarized radiating elements aredesigned to transmit and receive RF signals. Likewise, each array 232 offirst mid-band radiating elements 232, and each array 242 of secondmid-band radiating elements 242 may be configured to form a pair ofantenna beams, namely an antenna beam for each of the two polarizationsat which the dual-polarized radiating elements are designed to transmitand receive RF signals. Each linear array 220, 230, 240 may beconfigured to provide service to a sector of a base station. Forexample, each linear array 220, 230, 240 may be configured to providecoverage to approximately 120° in the azimuth plane so that the basestation antenna 100 may act as a sector antenna for a three-sector basestation. Of course, it will be appreciated that the linear arrays may beconfigured to provide coverage over different azimuth beamwidths. Whileall of the radiating elements 222, 232, 242, 1195 are dual-polarizedradiating elements in the depicted embodiments, it will be appreciatedthat in other embodiments some or all of the dual-polarized radiatingelements may be replaced with single-polarized radiating elements. Itwill also be appreciated that while the radiating elements areillustrated as dipole radiating elements in the depicted embodiment,other types of radiating elements such as, for example, patch radiatingelements may be used in other embodiments.

Some or all of the radiating elements 222, 232, 242, 1195 may be mountedon feed boards that couple RF signals to and from the individualradiating elements 222, 232, 242, 1195, with one or more radiatingelements 222, 232, 242, 1195 mounted on each feed board. Cables (notshown) and/or connectors may be used to connect each feed board to othercomponents of the antenna 100 such as diplexers, phase shifters,calibration boards or the like.

FIG. 9B is a rear or back view of the main backplane 210. RF connectorsor “ports” 140 are mounted in the bottom end cap 130 that are used tocouple RF signals from external remote radio units (not shown) to thearrays 220, 230, 240 of the passive antenna assembly 190. Two RF portscan be provided for each array 220, 230, 240 namely a first RF port 140that couples first polarization RF signals between the remote radio unitand the array 220, 230, 240 and a second RF port 140 that couples secondpolarization RF signals between the remote radio unit and the array 220,230, 240. As the radiating elements 222, 232, 242 can be slantcross-dipole radiating elements, the first and second polarizations maybe a −45° polarization and a +45° polarization.

A phase shifter 342 may be connected to a respective one of the RF ports140. The phase shifters 342 may be implemented as, for example, wiperarc phase shifters such as the phase shifters disclosed in U.S. Pat. No.7,907,096 to Timofeev, the disclosure of which is hereby incorporatedherein in its entirety. A mechanical linkage 344 may be coupled to a RETactuator (not shown). The RET actuator may apply a force to themechanical linkage 344 which in turn adjusts a moveable element on thephase shifter in order to electronically adjust the downtilt angle forone or more of the low-band or mid-band linear arrays 220, 230, 240.

It should be noted that a multi-connector RF port (also referred to as a“cluster” connector) can be used as opposed to individual RF ports 140.Suitable cluster connectors are disclosed in U.S. patent applicationSer. No. 16/375,530, filed Apr. 4, 2019, the entire content of which isincorporated herein by reference.

FIG. 9C illustrates the high-band radiating elements 1195 of the activeantenna assembly 1190. Note that the low-band radiating elements 222 may(partially) extend in front of the outer columns of high-band radiatingelements 1195. The low-band radiating elements 222 may have slanted feedstalks in some embodiments that allow the low-band radiating elements222 to be mounted on the primary reflector 214 while still extending infront of the high-band array 250/1195.

Referring to FIGS. 9C and 9D, the active antenna assembly 1190 caninclude an active antenna reflector 1172 that serves as the reflectorfor the high-band radiating elements 1190.

The reflector 170 and/or main reflector 214 of the passive antennaassembly 190 in the base station antenna 100 typically comprises a sheetof metal and is maintained at electrical ground. It acts to redirect RFradiation that is emitted backwardly by the radiating elements in theforward direction, and also serves as a ground reference for theradiating elements. When the active antenna is configured as a separateactive antenna module 110, the reflector 1172 of the active antennamodule 110 can be electrically coupled, upon assembly to the basestation antenna housing 100 h, to the reflector 170 of the passiveantenna assembly 190 so that the reflector 170 of the passive antennaassembly 190 and the reflector 1172 of the active antenna module 110 areat a common electrical ground reference.

The active antenna reflector 1172 can be spaced apart from the reflector170 (and/or main reflector 214) of the passive antenna assembly 190 (ina front to back direction) about a small gap space “g” that is typicallyin a range of about 3 mm-about 10 mm, in some embodiments.

Embodiments of the present invention configure the two reflectors 1172,170 as cooperating reflectors of the base station antenna 100. The tworeflectors 1172, 170 can be in close proximity to each other, once theactive antenna module 110 is assembled into the base station antennahousing 100 h, allowing the two reflectors 170, 1172 to electricallycouple to achieve the common ground reference. The active antenna module110 provides the reflector 1172 as a removable reflector from the basestation antenna housing 100 h. The reflector 1172 of the active antennamodule 110 can be configured to capacitively couple with a fixedreflector 170 in the base station antenna housing 100 h associated withthe passive antenna assembly 190.

The reflector 1172 of the active antenna module 110 can also serve inpart as a reflector for some radiating elements (e.g., low-bandradiating elements 222 at an upper portion of the base station housingadjacent the active antenna module 110) of the passive antenna assembly190. Thus, the reflector 1172 of the active antenna module 110 can bepart of the circuit of the passive antenna assembly 190.

The passive reflector 170 (214) and the active reflector 1172 can becapacitively coupled together, and thus the metal sheets forming thesereflectors can be physically spaced apart/separated. Collectively, thesefeatures can allow a) field replacement of the active antenna module 110and b) an interleaving of active/passive elements without increasing theoverall width of the base station antenna housing 100 h.

Referring to FIG. 9E, the outer perimeter of the reflector 1172 can beconfigured to couple with the reflector 170 (214) to be at a commonground reference. The coupling between the passive reflector 170 andreflector 1172 of the active antenna module 110 can be important to theperformance of the passive antenna. In some embodiments, portions of thetwo reflectors 170 and 1172 can overlap, with a very small gap, front toback, in order to facilitate strong capacitive coupling between the tworeflectors so that the two reflectors will be at a common groundreference.

The base station antenna 100 can have at least one radome 119 interposedbetween the two coupled reflectors 170, 1172.

Referring to FIG. 9E, the base station antenna 100 can be configuredwith a first radome 119 and a second radome 1129, spaced apart in afront to back direction, and positioned between reflectors 170, 1172.The first radome 119 can be part of the active antenna module 110 and beconfigured to seal the active antenna module 110. The second radome 1129can be configured to be a skin or middle/intermediate radome 1129 andcan be configured to seal the base station antenna housing 100 hcomprising the passive antenna assembly 190 at the receiving chamber 155(FIG. 3A). The second radome 1129 defines a seal covering over the openreceiving chamber 155 prior to coupling to the active antenna module110. The second radome 1129 can have a rigid, semi-rigid(self-supporting shape) or flexible configuration. The second orintermediate radome 1129 resides between the first radome 119 and thefront of the housing 100 f/external radome 150. When the active antennamodule 110 is assembled to the housing 100 h, both the first and secondradomes 119, 1129 can be internal to the housing 100 h.

In some embodiments, a foil and/or a metallized surface coating or thelike can be provided on or between one or more coupling surfaces ofreflectors 1172, 170 and/or radomes 1129 and 119 to improve capacitivecoupling, where desired or used. The radome 119 of the active antennamodule 110 can be a patterned radome with a series of laterally spacedapart peak and valley segments to reduce coupling of adjacent rows ofantenna elements and/or otherwise facilitate performance. Furtherdescription of patterned radomes can be found in co-pending U.S.Provisional Patent Application Ser. No. 63/083,379, the contents ofwhich are hereby incorporated by reference as if recited in full herein.

FIG. 9F illustrates an example embodiment of a radiating element 222(which may optionally be a low band element) having an angled feed stalk310. The radiating element 222 is positioned to extend over both thefirst and second reflectors 170(214) and 1172 according to embodimentsof the present invention. The first and second reflectors 170(214) canbe parallel, shown as co-planar. A lip or other shaped outer perimeterside segment 119 s of the radome 119 can extend laterally andlongitudinally under or over the side segment 170 s of the firstreflector 170(214).

FIG. 9G illustrates that the second reflector 1172 can have a laterallyextending side segment 1172 s. The side segment 119 s of the radome 119can extend between the side segment 1172 s of the second reflector 1172and the adjacent segment of the first reflector 170 s. The first andsecond reflectors 170(214) and 1172 can be capacitively coupled via theradome 119. The radome 119 can define a dielectric or be configured toprovide an air gap space or both to facilitate or provide the capacitivecoupling.

FIGS. 9H and 9I are greatly enlarged section views of example couplingsurfaces of a first reflector and second reflector interfaces of thedevice shown in FIG. 9E, 9F or 9G. FIG. 9H illustrates a horizontalcoupling configuration (in the orientation shown) between the horizontalsurface of the reflector 170 and the reflector 1172 of the activeantenna module 110. FIG. 9I illustrates a vertical couplingconfiguration (in the orientation shown) between the two reflectors 170and 1172. Stated differently, the coupling configurations can beprovided by one or both of surface area segments 1172 s, 170 s that areparallel to each other and may include one or more segments that areparallel to and/or perpendicular to a primary surface 1172 p, 170 p ofthe reflector 1172, 170, respectively.

FIGS. 9J-9O illustrate modifications to the coupling configurations thatincrease the surface area of the coupling segments 170 s, 1172 s of thereflector 1172 of the (removable) active antenna module 110 and the(fixed) reflector 170(214) of the base station antenna housing 100 h.

FIGS. 9M-9O illustrate that an inner side wall 170 w can be provided bythe passive reflector 170. The side wall 170 w can be perpendicular tothe primary surface 170 p of the reflector 170.

The coupling of the reflectors 1172, 170 can allow the separateinstallation of the reflectors and can be configured to use anycapacitive coupling and may include a plate capacitor typeconfiguration.

Referring to FIGS. 10A and 10B, the active antenna module 110 can beinstalled by aligning the active antenna module 110 with the recessedsegment 108 over the chamber 155 and inserting the active antenna module110 toward the front 100 f of the housing 100 h so that the activeantenna module 110 seals to the antenna housing 100 h at the recessedsegment 108. The inserting may be done manually by pushing inward in asingle step without requiring tools. Properly engaged, theinserting/pressing can also seal the active antenna module 110 to thehousing 100 h.

When installed as shown in FIG. 10B, the active antenna module 110 isexternally accessible and has an outermost extent that is in a plane P1that is different from a plane P2 of a primary outer surface 151 p ofthe second segment 151 of the radome 150 (shown as the lower portion).In some embodiments the plane P1 is at a distance D1 from a primarysurface of the front 100 f of the housing 100 h and P2 is at a distanceD2 from the primary surface of the front 100 f of the housing 100. D1-D2can be in a range of about (−1) inch to about (+6) inches, such as about+0.25 inches, +0.5 inches, +1, +2, +3, +4, +5 or +6 inches. Thus, theactive antenna module 110 can project a relatively small distanceoutward from the lower portion of the rear of the radome 150, be flushwith (e.g., co-planar), or recessed with respect to, the plane P2 tothereby provide a compact configuration and/or to avoid an offset ofcenter of gravity of the base station antenna housing 100 h.

FIG. 23C shows the rear 110 r of the active antenna module 110 at afirst distance D1 and FIG. 25C shows the rear 110 r of the activeantenna module 110 at a greater second distance D2 from the rear surface100 r of the housing 100 h, both coupled to internal rails 180 in thehousing 100 h via an adapter member(s) 2900, 2900′ that is/are attachedto the active antenna module 110. That is, different configurations ofthe active antenna module 110 with radio circuitry 1120 can mountdifferent distances from the rear 100 r of the antenna housing 100making the product narrower or thicker at that location. The adaptermember 2900, 2900′ can be configured to position the radome 119 atsubstantially the same location, such as within about (+/−) 1-10 mm, inthe housing 100 h facing the external radome 150 and/or front of thehousing 100 f.

The plane P1 can be recessed, flush with or project outward from therear surface 120 r of the top 120 of the antenna housing 100 h,optionally the same distance or a greater distance as the outer primarysurface 151 p of the second segment 151 of the radome 150, e.g., D1-D2.

FIGS. 11A-11D illustrate an example sequence of actions that can be usedto install an active antenna module 110 to a base station antenna 100while the base station antenna 100 is held by a mounting structure 300.The base station antenna 100 can include mounting hardware 310 attachedto a rear 100 r of the housing 100 h. The active antenna module 110 canalso include mounting hardware 310 and it can be coupled to the mountingstructure 300 after it is attached to the base station antenna 100 (FIG.11D).

The active antenna module 110 can be provided and/or installed as astandalone unit or in an assembled active/passive configuration whenmounted to the base station antenna 100. The base station antennahousing 100 h can be installed without the active antenna module 110 forfuture upgrade.

FIGS. 12A and 12B illustrate an example of another embodiment of anactive antenna module 110′ that can include a second radome 1119 asdiscussed above. Also, the active antenna module 110′ can optionally beconfigured to mount to the housing 100 h without requiring a sealedinterface and the corresponding receiving recessed segment 108 may havea closed rearward facing surface.

Pursuant to further embodiments of the present invention, base stationantennas 100 are provided which have one or more active antenna modules110 mounted on the back 100 r of the antenna 100. FIG. 13 is a rearperspective view of a base station antenna 100″ comprising a pair ofactive antenna modules 110 mounted on the rear 100 r, shown mounted inrespective recessed segments 108.

FIG. 14 illustrates another embodiment with a recessed segment 108 andan active antenna module 110 can extend over more than a major portionof the length of the rear 100 r of the antenna 100′″.

In some embodiments, the base station antennas may be designed so that avariety of different active antenna modules 110 can be used in a givenantenna 100. The active antenna module 110 can be manufactured by anyoriginal equipment manufacturer and/or cellular service provider andmounted on the back of the antenna. This allows cellular operators topurchase the base station antennas and the radios mounted thereonseparately, providing greater flexibility to the cellular operators toselect antennas and radios that meet operating needs, price constraintsand other considerations.

The antennas 100 may have a number of advantages over conventionalantennas. As cellular operators upgrade their networks to support fifthgeneration (“5G”) service, the base station antennas that are beingdeployed are becoming increasingly complex. It is desirable to minimizeantenna size and/or integrate increased number of antenna or antennaelements inside a single radome. For example, due to space constraintsand/or allowable antenna counts on antenna towers of existing basestations, it may not be possible to simply add new antennas to support5G service. Accordingly, cellular operators are opting to deployantennas that support multiple generations of cellular service byincluding linear arrays of radiating elements that operate in a varietyof different frequency bands in a single antenna. Thus, for example, itis common now for cellular operators to request a single base stationantenna that supports service in three, four or even five or moredifferent frequency bands. Moreover, in order to support 5G service,these antennas may include multi-column arrays of radiating elementsthat support active beamforming. Cellular operators are seeking tosupport all of these services in base station antennas that arecomparable in size to conventional base station antennas that supportedfar fewer frequency bands.

Pursuant to still further embodiments of the present invention, methodsof assembling beamforming radios on base station antennas to providebase station assemblies are provided. Methods of installation areprovided that are suitable for factory installation as well as methodsfor field installing (or replacing) beamforming radios on base stationantennas. In the discussion that follows the installation methods willprimarily be described with reference to installing the active antennamodules 110 with beamforming radios to base station antenna 100. It willbe appreciated, however, that these techniques may be used for any ofthe other embodiments disclosed herein, with suitable modifications madeas appropriate.

The active antenna modules 110 may also be readily replaced in thefield. As is well known, base station antennas are typically mounted ontowers, often hundreds of feet above the ground. Base station antennasmay also be large, heavy and mounted on antenna mounts that extendoutwardly from the tower. As such, replacing base station antennas maybe difficult and expensive. The active antenna modules 110 withbeamforming radios may be field installable and/or replaceable withoutthe need to detach the base station antenna 100 from an antenna mount.

Turning now to FIG. 15 , a flow chart of example actions that can beused to install a base station antenna is shown. A base station antennahousing comprising a passive antenna assembly is provided (block 600).An active antenna module is attached to the base station antenna housingwith the active antenna module being held in a recessed segment and withat least a rear portion thereof being external to the base stationantenna housing to define a base station antenna (block 610).

The base station antenna housing can have a rear surface with a recessedregion overlying an internal chamber with components of a passiveantenna assembly and the attaching step is carried out to place an innerfacing surface of the active antenna module in or against the recessedregion (block 612).

The attaching step can be carried out to sealably attach the activeantenna module to the base station antenna housing to thereby provide awater-resistant or water-tight coupling (block 614).

The active antenna module can comprise mounting brackets that couple toa mounting structure for field operation (block 616).

The base station antenna housing can include a base plate with anaperture and a perimeter portion surrounding the aperture and the activeantenna module can sealably couple to the perimeter portion of the baseplate when attached to the antenna housing (block 618).

The base station antenna housing can be configured to interchangeablyaccept different active antenna modules (block 620).

A user can be allowed to remove the active antenna module and replace itwith a different active antenna module at a field site while the basestation antenna is coupled to a mounting structure at the field site(block 622).

Turning now to FIGS. 16A, 16B, 17A, 17B and 18 , the active antennamodule 110″ can be configured to be slidably inserted and coupled to thebase station antenna 100 from the top 100 t of the base station antenna.The rails 180 ₁, 180 ₂ can be exposed external rails 180″ (prior toassembly with the active antenna module 110″) that slidably (matably)couple to longitudinally extending rail couplers 1220. The rail couplers1220 are provided as a pair, one that extends along a respective rightor left side 110 r, 110 l, of the active antenna module 110″. The railcouplers 1220 can reside between the (inner) radome 119 and the rearsurface 110 r of the active antenna module 110″. Other slidingdetachable configurations may be used, including sliding from a bottom100 b instead of the top 100 _(t) or sliding from both top and bottomends, one form each direction, if more than two active antenna modules110 are used.

Similar to the embodiment shown in FIGS. 8A-8F, upon assembly, theactive antenna module 110″ is (sealably) coupled to the upper portion ofthe base station antenna 100. However, no screws or pins are required tomount the active antenna module 110′ to the seal perimeter interface 100i surrounding the receiving cavity 155. This top-slide-to-coupleconfiguration may facilitate field assembly and/or reduce alignmentissues when retrofitting in the field.

First and second arrays (columns) 220-1, 220-2 of low band radiatingelements 222 reside on right and left side portions of the base stationantenna on each side of the receiving recessed region of a rear of thehousing 100 r and/or chamber or cavity 155 (see also, FIGS. 9A, 23C,25C). The outer perimeter shape of the radome 119 can be configured toslide past some of these radiating elements and extend adjacent thereto.A seal member 112 can reside on one or both of an inner facing surfaceof the active antenna module 110″ and the seal interface 100 i of thebase station antenna housing 100 h surrounding the receiving chamber orcavity 155.

The base station antenna housing 100 h can include cross-segments 169extending across lower and upper ends of the receiving chamber/cavity155, which may optionally form part of the housing seal interface 100 i.

In some embodiments, the active antenna module 110″ comprises aninwardly projecting top member 1225 that can couple to and/or definepart of the top 120 of the base station antenna 100 and provide amoisture resistant seal and/or top end cap. The top member 1225 canextend inward a further distance than the radome 119.

A length of the housing 100 h, typically including the top 100 t of thebase station antenna housing 100 h can have an open or closed “U”like-shape that slidably receives the active antenna module 110″. Thesides of the “U” shape correspond to the rearwardly projecting sidewalls 101, 103 (FIG. 5 ) of the housing 100 h and extend a distance thatis less than the lateral extent of the bottom of the “U” shape and withthe bottom defined by a front 100 f of the housing 100 h. The top of theU shape can be closed across one or more locations using a cross-member169 for increasing structural rigidity (FIG. 30A).

The top of the active antenna module 110″ can be configured in othermanners as can the top of the base station antenna housing to provide asuitably water-tight seal. For example, a removable end member with aseal such as a gasket or a pivoting top member with a seal such asgasket can be attached to the top of the base station antenna to open toallow the active antenna module 110″ to be slidably inserted or removed(not shown).

FIGS. 16A, 16B, 17A and 17B illustrate that the base station antennahousing 100 h can further include rearwardly projecting side members1310 that extend rearward of the rails 180 ₁, 180 ₂ and that also extendlongitudinally for a sub-length of the antenna housing 100 h, one oneach side of the receiving cavity 155. The side members 1310 couple tomounting hardware 310. The active antenna module 110″ can be fullysupported by the antenna housing 100 h when mounted to the mountingstructure 300 without requiring mounting hardware attached to the activeantenna module 110″ itself.

The mounting hardware 310 can include arms 310 a that project outwardly(toward a rear 100 r of the housing 100 h) a distance sufficient todefine a small clearance gap between a rear surface 110 r of the activeantenna module 110″ and the mounting structure 300 to thereby allow theactive antenna module 110′ to be slidably advanced (or retracted forreplacement) between the mounting structure 300 and the mountinghardware 310 when the base station antenna housing 100 h is mounted in afield use orientation.

FIG. 18 illustrates that the active antenna module 110″ can includemounting hardware 310 coupled to its rear surface 100 r and thismounting hardware 310 can be used to mount it to the mounting structure300 after it is attached to the base station antenna 100.

Combinations of the mounting configurations shown in FIGS. 17A, 17B and18 for mounting the active antenna module 110″ to the mounting structure300 may also be used.

At least one of the first reflector 170 or the second reflector 1172 canbe provided by a frequency selective surface and/or substrate that isconfigured to allow RF energy (electromagnetic waves) to pass through atone or more first defined frequency range and that is configured toreflect RF energy at a different second frequency band. The frequencyselective surface and/or substrate may be interchangeably referred to asa “FSS” herein. Thus, a reflector, such as one or both of the passivereflector 170 and/or the active antenna reflector 1172, of the basestation antenna 100, can reside behind at least some antenna elementsand can selectively reject some frequency bands and permit otherfrequency bands to pass therethrough by including the frequencyselective surface and/or substrate to operate as a type of “spatialfilter”. See, e.g., Ben A. Munk, Frequency Selective Surfaces: Theoryand Design, ISBN: 978-0-471-37047-5; DOI:10.1002/0471723770; April 2000,Copyright© 2000 John Wiley & Sons, Inc. the contents of which are herebyincorporated by reference as if recited in full herein.

The frequency selective surface and/or substrate material 1500 of arespective reflector can comprise metamaterial, a suitable RF materialor even air (although air may require a more complex assembly). The term“metamaterial” refers to composite electromagnetic (EM) materials.Metamaterials may comprise sub-wavelength periodic microstructures.

The FSS material can be provided as one or more cooperating layers. TheFSS material can include a substrate that has a dielectric constant in arange of about 2-4, such as about 3.7 and a thickness of about 5 mil andmetal patterns formed on the dielectric substrate. The thickness canvary but thinner materials can provide lower loss.

The first reflector 170 and the second reflector 1172 can be parallel,optionally co-planar, and one or both can comprise an FSS.

The first reflector 170 (of the passive antenna housing 100 h) cancomprise a frequency selective substrate 170 f and can be physically(e.g., integral with) and/or electrically coupled to the primaryreflector 214 of the passive antenna assembly 190.

The first reflector 170 of the passive antenna 100 can comprise thefrequency selective surface or substrate 170 f and can reside forward ofthe reflector 1172 of the active antenna module 110, e.g., closer to thefront 100 f of the housing 100 h than the reflector 1172 of the activeantenna module 110.

In some embodiments, the second reflector 1172 can reside closer to thefront 100 f of the housing 100 h than the reflector 170 of the passiveantenna assembly 190, when assembled to the passive antenna assemblyhousing 100.

Turning now to FIGS. 19A and 19B, the reflector 170 of the passiveantenna assembly 190 in the base station antenna 100 can be configuredto have a FSS material 1500 to define a frequency selective substrateand/or surface 170 f This configuration does not require electrical,e.g., capacitive, coupling between the second reflector 1172 (reflectorof the active antenna module 110) and the first reflector 170 (areflector of the passive antenna assembly 190).

Optionally, the second reflector 1172 may be configured to have afrequency-selective surface and/or substrate 1172 f.

In some embodiments, the FSS material 1500 of the frequency selectivesubstrate/surface 170 f of the reflector 170 of the passive antennaassembly 190 can be configured to act like a High Pass Filteressentially allowing low band energy to completely reflect (the FSS canact like a sheet of metal) while allowing higher band energy, forexample, about 3.5 GHz or greater, to completely pass through. Thus, thefrequency selective substrate/surface is transparent or invisible to thehigher band energy and a suitable out of band rejection response fromthe FSS can be achieved. The FSS material 1500 may allow a reduction infilters or even eliminate filter requirements for looking back into theradio 1120.

In some embodiments, the reflector 170 with the FSS 170 f may beimplemented by forming the frequency selective surface on a printedcircuit board, optionally a flex circuit board. In some embodiments, thereflector 170, for example, may be implemented as a multi-layer printedcircuit board, one or more layers of which formed with a frequencyselective surface 170 f configured such that electromagnetic waveswithin a predetermined frequency range cannot propagate through thereflector 170, and wherein one or more other predetermined frequencyrange associated with the one or more layers of the multi-layer printedcircuit board is allowed to pass therethrough.

FIG. 20A shows an example low band antenna element 222 with dipole armsresiding in front to the frequency selective substrate and/or surface170 f FIG. 20B shows an example high band antenna element 252 residingbehind the frequency selective substrate and/or surface 170 f and infront of the reflector 1172 of the active antenna module 110. Thisconfiguration can avoid electrically coupling a passive reflector 170for the low-band arrays 220 and an active reflector 1172 for the higherband arrays. Instead, the frequency selective substrate and/or surface170 f can extend a full width of the antenna and the higher band/highband active antenna 1195 (e.g., HB/3.5 GHz) forward of the activereflector 1172 can transmit RF energy through this frequency selectivesubstrate and/or surface (FSS) 170 f.

The frequency selective substrate and/or surface 170 f can reside adistance in a range of ⅛ wavelength to ¼ wavelength of an operatingwavelength behind the low band dipoles 222, in some embodiments. Theterm “operating wavelength” refers to the wavelength corresponding tothe center frequency of the operating frequency band of the radiatingelement, e.g., low band radiating element 222.

Referring to FIGS. 20C and 20D, the FSS material 1500 of a respectivereflector 170 of the passive antenna housing 100 h and/or reflector 1172of the active antenna module 110, for example, can comprise a substrate1500 s having a layer or layers thereon that can have partial or fullpatterns 1500 p of patches 1502 and a metallic grid 1530 to providefrequency selection characteristics for a FSS reflector. As shown, thesubstrate 1500 s is a dielectric material with metal patterns of patches1502 and the metallic grid 1530. The patterns 1500 p can be configuredto allow some frequencies to go through the reflector and somefrequencies to be reflected to thereby provide frequency selectivesurfaces and/or substrates. The pattern 1500 p may change in differentareas of the FSS material 1500 of a respective reflector, such as thepassive antenna reflector 170, and in some areas there may be no patternand a full or partially full metal sub-surface area or full or partiallyfull metal layer can exist in those areas.

The pattern 1500 p provided by the FSS material 1500 can be the same ordifferent in size and/or shapes of patches 1502 over respective areas orsub-areas and/or on different layers. The shapes of patches 1502 and theshape of the elements of the metallic grid 1530 can be, e.g., polygonal,hexagonal, circular, rectangular or square and each can be formed ofmetal.

The pattern 1500 p can be configured so that there is a perimeter gapspace 1503 separating neighboring patches 1502 ₁, 1502 ₂, for example.The grid 1530 may subdivide the gap space 1503 into “islands” ofdielectric material that surround each patch 1502. The gap spaces 1503may comprise regions of a dielectric substrate on which no metal isdeposited. The metallic grid 1530 can be embedded inside the gap spaces1503 between patches 1502. This metallic grid 1530 can be printed on theopposite side of the substrate 1500 s and does not need to be on thesame side of the substrate that patches 1502 are on.

The pattern 1500 p can be provided by one layer or by different layersthat cooperate to provide the frequency selective characteristics thatcan substantially prevent the electromagnetic waves within a firstoperational frequency band from passing through the reflector material1500 while allowing the electromagnetic waves within a secondoperational frequency band to pass through the reflector material 1500.

In some embodiments, the pattern 1500 p of patches 1502 can be providedas an array of closely spaced apart geometric shaped patches 1502.

The patches 1502 can be provided by copper etched on the substrate 1500s. In some embodiments, the pattern 1500 p of patches 1502 can beconfigured so that the patches 1502 are held by a honeycomb or web ofmaterial to suspend the patches 1502 without requiring a physicaloverlying or underlying base substrate.

The FSS material 1500 can comprise two structures which are printed onthe same side or on opposing sides (opposing primary surfaces) of thesubstrate 1500 s. One structure can be a pattern of hexagons forming thepatches 1502 and the other structure can be a mesh or grid 1530 thatlooks like a honeycomb structure.

The grid 1530 can optionally be positioned in front of, behind orbetween one or more adjacent layers providing the pattern 1500 p ofpatches 1502. Where a grid 1530 is used, it can be metallic and can beplaced or formed on a top or bottom layer of the substrate 1500 s and/orbehind a rearwardmost patch 1502 (closest to the rear 100 r of thehousing 100 h) or in front of a forwardmost patch 1502 (closest to thefront 100 f of the housing). The term “grid” means an open cell orlattice type structure. The term “thin grid” means that the grid has athickness (e.g., width in a lateral dimension and/or a depth in a frontto back direction of the housing 100 h of the base station antenna 100)that is in a range of about 0.01 mm and 0.5 mm, such as, for example,about 0.1 mm.

As shown, the relatively large patches 1502 are metal, e.g., copper, andthe adjacent region is the gap 1503 which can be defined by an exposedsubstrate. The grid element 1530 e is spaced apart from neighboringpatches 1502 by a grid element 1530 e. The patches 1502 are metal andthe thin grid 1530 is also metal, typically the same metal but differentmetals can be used. The area between the patches 1502 and the gridelements 1530 e is the gap 1503 and the area of the gap 1503 betweenadjacent patches 1502 can have a lateral extent that is less than thearea of the patch 1502 and greater than the grid element 1530 e.

FIGS. 21A and 21B illustrate that the frequency selectivesubstrate/surface 170 f can be configured with cutouts or channels 2170that allow the substrate 170 f to be slid into place or otherwiseassembled about the feed boards 1200 and/or feed stalks 222 f of thedipole antenna elements 222. The frequency selective substrate/surface170 f can be provided as single piece device or as a multiple piecedevice. For example, the FSS reflector 170 f can be provided as aplurality of segments that can be assembled together and shaped withcutouts for the stalks 222 f.

As shown in FIGS. 19A/19B, the frequency selective substrate/surface 170f can reside closer to a front 100 f of the housing 100 h than the mainreflector 214 of the passive antenna assembly 190. The reflector 1172 ofthe active antenna module 110 can be stacked behind the frequencyselective substrate/surface 170 f and may reside inside or adjacent therear surface of the housing 100 h. The FSS 170 f can be capacitivelycoupled to the main reflector 214.

In other embodiments, referring to FIGS. 22A and 22B, the frequencyselective substrate/surface 170 f can be coplanar with the mainreflector 214. The active antenna module 110 can reside a furtherdistance outside the rear surface 100 r of the housing 100 h. Thereflector 1172 in the active antenna module 110 can reside outside thehousing 100 h, stacked behind the frequency selective substrate/surface170 f. The dipole radiators of the low-band radiating elements 222 canreside in front of the frequency selective surface. In some embodiments,no channels for the feed stalks 222 f are required to be formed in thefrequency selective substrate 170 f.

Referring to FIG. 21C, the FSS material 1500 can be provided as aprinted circuit board 1500 c. The FSS material 1500 can be configured sothat predetermined frequency ranges that are passed or blocked by theone or more metal layers 1501, 1502, 1503, 1504 of the multi-layerprinted circuit board 1500 c may be different from one or more otherlayers. In some embodiments, the predetermined frequency ranges passedor blocked by the one or more layers of the multi-layer printed circuitboard may not overlap with one another. In some embodiments, thepredetermined frequency ranges passed or blocked by the one or morelayers of the multi-layer printed circuit board may at least partiallyoverlap with one another. In such embodiments, each layer in themulti-layer printed circuit board that is formed with a frequencyselective surface is equivalent to a “spatial filter”, and the entiremulti-layer printed circuit board equivalently comprises a plurality ofcascaded “spatial filters”, wherein each “spatial filter” is configuredto either allow or stop (i.e., passes or substantially attenuates and/orreflects) a part of the first operational frequency band, therebycollectively substantially allowing or preventing the electromagneticwaves within a respective defined operational frequency band to eitherpassing through or be blocked/reflected by the reflector. As such, thedesign for the frequency selective surface of each layer of themulti-layer printed circuit board 1500 c may be simplified whileensuring that the electromagnetic waves within defined one or moreoperational frequency bands are reflected/substantially blocked by thereflector material 1500 or allowed to pass through the reflectormaterial 1500.

In some embodiments, the reflector material 1500 may comprise adielectric board 1500 d having opposed first and second primary surfaces1510, 1512 that both reside behind the radiators of respective columnsof first radiating elements 220-1, 220-2 where one or both primarysurface 1510, 1512 can comprise a periodic conductive structure thatforms the frequency selective surface. The periodic conductivestructures can be on both the first and second primary surfaces to formthe frequency selective surface of the reflector material 1500.

In some embodiments, the FSS material 1500 may comprise a plurality ofreflector units that are arranged periodically, where each unit maycomprise a first unit structure forming the periodic conductivestructure on the first primary surface of the dielectric board and asecond unit structure forming the periodic conductive structure on thesecond primary surface of the dielectric board. A position of the firstunit structure may correspond to a position of the second unitstructure. In some embodiments, as viewed from a direction perpendicularto the first and second primary surfaces, the center of each first unitstructure coincides with the center of corresponding second unitstructure.

In some embodiments, the first unit structure may be equivalent to aninductor (L), the second unit structure may be equivalent to a capacitor(C), thereby the reflector unit comprising the first unit structure andthe second unit structure that are correspondingly disposed may beequivalent to an LC resonant circuit. In some embodiments, the reflectorunit may be configured to be equivalent to a parallel LC resonantcircuit. A frequency range that the frequency selective surface allowsto pass therethrough may be adjusted to a desired frequency range bydesigning the equivalent inductance of the first unit structure and theequivalent capacitance of the second unit structure.

In some embodiments, the traveling radio frequency wave that goesthrough the FSS material 1500 can see a shunt LC resonator and atransmission line (substrate having an impedance Zo depending on itsthickness). The capacitance of each unit cell can be made/defined by orformed from the coupling across the gap between the grid and the patch.The inductor can be made out of the metallic thin lines of the grid.

The mesh/grid can define a high pass filter and the patches can define alow pass filter, together defining a band pass filter. A multiple layerprinted circuit board having multiple FSS structures can be used for asharper filter response.

In some embodiments, the periodic conductive structure on the firstprimary surface of the dielectric board comprises a grid (arraystructure) 1530, the first unit structure comprises a grid element 1530e serving as a repetition unit in the grid array structure 1530, and theperiodic conductive structure on the second primary surface of thedielectric board comprises a patch array pattern and/or structure 1500p, the second unit structure comprises a patch 1502 serving as arepetition unit in the patch array structure 1500 p. For example, thegrid element 1530 e of the first unit structure may have an annularshape of a regular polygon such as a square, the patch 1502 of thesecond unit structure may have a shape of a regular polygon such as asquare.

Several exemplary configurations of the frequency selective surfacematerial 1500 of the reflector 170 f of base station antennas 100according to some embodiments of the present disclosure are described indetail below with reference to FIG. 21D.

For example, as shown in FIG. 21D, the reflector material 1500 cancomprise a set of reflector units 1500 u. A respective reflector unit1500 u can be configured to have a periodic (conductive) and/or unitstructure on a first primary surface 1510 and a periodic (conductive)and/or unit structure on the second primary surface 1512. The unitstructure on the first primary surface 1510 can be a grid element 1530 eof a metal grid 1530 and the unit structure on the second primarysurface 1512 can be a metal patch 1502. The shapes and sizes of alignedpairs of the unit structures of a respective reflector unit 1500 u canbe the same or different, shown as the same size and shape. For example,the reflector unit 1500 u can have a square grid providing square gridelements 1530 e and a square patch 1502 (second unit structure) atcorresponding positions on both sides/primary surfaces 1510, 1512 of adielectric board. As viewed from a direction perpendicular to the firstand second primary surfaces 1510, 1512, the center of the square grid1530 coincides with the center of the square patch 1502. Such areflector unit 1500 u may be configured to be equivalent to a parallelresonant circuit formed by an inductor (the square grid) and a capacitor(the square patch). The magnitudes of the inductance of the inductor andthe capacitance of the capacitor of the equivalent parallel resonantcircuit may be determined based on desired frequency selectivity of thefrequency selective surface, and then the sizes of the grid elements1530 e and the patches 1502 can be determined accordingly. In theexample of FIG. 21D, the reflector material 1500 is shown to includereflector units 1500 u in three rows and eight columns, however, it willbe appreciated that this is a non-limiting example, the arrangement ofthe reflector units may be determined based on designed sizes of theunit structures.

In the example patterns shown in FIG. 21D, conductive materials arepresent at positions of black lines (metal grid 1530) and black patches(blocks) 1502 and are not present at white positions. Conductivematerials may be deposited at both sides of a dielectric board and thenrespective patterns may be formed by etching technologies such asphotolithography or FIB milling, thereby forming periodic conductivestructures to realize the frequency selective surface. Any othersuitable methods currently know or developed later in the art may beemployed to form desired periodic conductive structures on thedielectric board. The periodic conductive structures may be formed usingany suitable conductive materials, typically using metal such as copper,silver, aluminum, and the like. The dielectric board may employ, forexample, a printed circuit board. The thickness, dielectric constant,magnetic permeability and other parameters of the dielectric board mayaffect the reflective or transmissive properties at desired operatingfrequencies.

Referring to FIGS. 22C-22H, a portion of a base station antenna 100 isshown with the passive antenna assembly 190 comprising a primaryreflector 214 and the FSS material 1500 that is adjacent the primaryreflector 214 providing passive reflector 170 f. The primary reflector214 of the passive antenna assembly 190 can be configured to have upperextensions forming metal reflector side segments 170 s that can becoupled to the FSS material 1500. Feed boards 1200 can be provided infront of or behind the side segments 170 s. The feed boards 1200 connectto feed stalks 222 f of radiating elements 222 (such as low bandelements). The feed stalks 222 f can be angled feed stalks 221 thatproject outwardly and laterally inward to position the front end of thefeed stalks 221 closer to center of the reflector 170 f than a rearwardend. The feed boards 1200 can be coupled and/or connected to the FSSmaterial 1500.

The feed boards 1200 can sit behind or in front of the FSS 1500 and canbe capacitively coupled to the metal passive reflector(s) 170 s, 214.The FSS material 1500 can be installed in front of or behind thereflector segments 170 s and may be capacitively coupled to the passivereflector 170 s, 214.

The FSS material 1500 can extend parallel to the side walls 103 of thebase station antenna housing 100 h. The reflector side segments 170 scan have an “L” shape and/or orthogonal segments as shown in FIG. 22H,for example, and the “L shaped and/or orthogonal segments can bothcomprise the FSS material 1500. The FSS material 1500 can form part ofany reflector or interior side wall supporting radiating antennaelements, particularly where there are antenna elements in front and/orbehind the FSS material 1500.

FIG. 22G illustrates that the FSS material 1500 can have a perimeterwith sides having channels (or cut outs) 2170, some having a greaterlength dimension than others, that allow connectors and/or cables of thefeed boards and/or the feed stalks 222 f to extend from the feed boardsthrough the channels 2170. Referring to FIGS. 22E and 22F, the left andright-side longitudinally extending perimeters of the FSS material 1500can extend in front of or behind the corresponding (right and left) sidesegments 170 s of the metal passive reflector 170/214. In someembodiments, the passive reflector 170 can have elongate, longitudinallyextending openings 1170 on each side that can be configured to allow thefeed stalks 222 f to extend forward therethrough.

Feed boards 1200 can be provided that extend a distance in front of theside segments 170 s and that can connect to feed stalks 222 f ofradiating elements 220 (such as low or mid band radiating elements). Thefeed stalks 222 f can be angled feed stalks that project outwardly andlaterally inward to position the front end of the feed stalks 222 fcloser to a lateral center of the reflector 170 f than a rearward end.The feed boards 1200 can be connected to the reflector 170 f and/ormetal side segments 170 s. The feed boards 1200 can be parallel to thereflector 170 f and positioned laterally on each side thereof as shown.

In some embodiments, as shown in FIG. 22I, the reflector 170 f can beconfigured with a metal pattern 1500 p that merges into side segments orareas of full metal 2170 which may be shaped as laterally extendingmetal tabs with front and/or back surfaces fully metallized. The areasof full metal 2270 can couple, for example, capacitively couple, to thelongitudinally extending side segments 170 s of the passive (primary)reflector 214 residing on right and left sides of the base stationantenna.

In some embodiments, as shown in FIG. 22J, the feed boards 1200 can beorthogonal or substantially orthogonal (+/−15 degrees) to the reflector170 f with the patches 1500 p. In this orientation, the feed boards 1200can be positioned adjacent and parallel to or substantially parallel to(+/−30 degrees) the side walls 103 of the base station antenna joiningthe front radome 150 and the back 100 r of the base station antenna.Antenna elements 222 can extend laterally inward over the reflector 170f. This configuration may reduce blockage of high band energy at highscan angles. A laterally wide, e.g., whole width or substantially wholewidth (substantially full width meaning +/−15% of a full width of thebase station antenna), reflector 170 f may be used so that the FSSreflector material 170 f extends laterally outward a distancecorresponding to a lateral width of the base station antenna.

It is also noted that feed boards 1200 are not required and small orminiature power dividers with cables can be used in lieu of feed boards.

Turning now to FIGS. 23A-23C, 24, 34 and 35A-35C, the active antennamodule 110 can comprise at least one adapter member 2900. As shown, theat least one adapter member 2900 can be provided as a pair of adaptermembers, one attached to each of the right and left sides of the activeantenna module 110. The radome 119 of the active antenna module 110 canreside in front of the at least one adapter member 2900. As shown, theat least one adapter member 2900 includes a planar surface 2904 thatprojects laterally out from the active antenna module 110. The planarsurface 2904 resides on the rail 180 of the antenna housing 100 h.Fixation members 2903 that extend through apertures 2902 in the adaptermember 2900 can be used to attach the adapter member 2900 to the activeantenna module 110.

In some embodiments, a lower edge 2901 of the adapter member 2900 cancomprise a pair of spaced apart prongs 2901 p with a gap space 2901 gthat slidably receives a pin 189 that projects inwardly from arespective rail 180 (FIG. 35A). This lower edge 2901 can define asupport point and a rotation center for assembling the active antennamodule 110 to the housing 100 h for ease of field installation. The pin189 can have a polymeric jacket 189 j to avoid metal to metal contactwith the active antenna module 110. The active antenna module 110 can beprovided at a number of different angles relative to the housing 100 h,and as indicated by arrow “A”, slid down until the lower edge 2901engages the pin 189 and defines a stop, at which time, the activeantenna module 110 can be rotated into position, as indicated by arrow“B”, optionally with at least the radome 119 thereof positioned in thereceiving chamber 155 of the housing 100 h. Once in position, fixationmembers 288 can be inserted through the flat surface 2904 into the rail180 (FIG. 24 ).

FIGS. 25A-26 show another configuration of the active antenna module 110and another configuration of the at least one adapter member 2900′. Asshown, the at least one adapter member 2900 can be provided as singleadapter member that defines a frame body with a lower end 2909 and anupper end 2910. Right and left sides of the adapter member 2900′comprise at least one outwardly extending planar surface 2904. In theembodiment shown, there are two laterally outwardly extending, parallelplanar surfaces 2904 on each of the right and left side. As shown inFIGS. 25C, 28B, the first surface 29041 (facing the front of the housing100 h) has a greater laterally extending length than the second surface2904 ₂ and resides on the rail 180 and can be affixed to the rail 180via fixation member 288. A first end 2909 of the adapter 2900′ can havea pair of outwardly extending lips 29091. One lip 29091 can project outfurther than the other and can attach to the body of the active antennamodule 110 while the other lip 29091 attaches to the radome 119. Thesecond opposing end 2910 can be planar and devoid of any lips oroutwardly projecting surfaces as shown in FIG. 25A.

The adapter 2900′ can surround a calibration circuit board 2980 (FIG.25B) that can be held between the radome 119 and the radio 1120 of theactive antenna module 110.

Referring to FIGS. 23C and 25C, the rails 180 can be provided with arail frame 180 f with a first rear facing surface 182 that abuts theplanar surface 2904 of the adapter 2900, 2900′. The rail frame 180 f canalso include a second front facing, laterally inwardly extending planarsurface 184 that extends inwardly a distance greater than the first,rear facing, surface 182. This second surface 184 can couple to thesecond planar surface 2904 ₂ of the adapter 2900′.

Referring to FIGS. 27B, 28B and 40 , the rail frame 180 f can beconfigured to sealably couple to the intermediate radome 1129. Acurvilinear laterally extending extension 1129 c of the intermediateradome 1129 can extend in a curvilinear channel 186 of the rail frame180 f.

The rail frame 180 f can releasably or detachably attach to a number ofdifferent shaped adapter members 2900, 2900′ allowing for differentshapes and size and configurations of the active antenna module 110 tobe coupled to the antenna housing 100 h. FIGS. 23C, 25C, 27A and 28Aillustrate that depending on the adapter member 2900, 2900′ and theactive antenna module 110, the rear 110 r of the active antenna module110 can project out of the rear surface 100 r of the housing 100 h atdifferent distances D1, D2, as shown, while placing the radome 119 ofthe active antenna module 110 at substantially the same position (+/−1mm-5 mm) in the housing 100 h facing the external radome 150 of thefront 100 f of the housing. The distance D2 can be 2-6 inches greaterthan D1 in some embodiments.

Still referring to FIGS. 23C and 25C, the base station antenna 100 canalso include arrays of low band radiating elements 220-1, 220-2 on eachside of the inner radome 119, and additional radiating elements 232residing between the front of the housing 100 h/external radome 150 andthe intermediate radome 1129 and radome 119 of the active antennamodule.

As shown in FIGS. 23C and 25C, pursuant to embodiments of the presentinvention, low-band radiating elements 220-1, 220-2 are provided thatinclude “tilted” or “angled” feed stalks 221 that can have at least onesegment that extends at an oblique angle from the reflector 170.Generally stated, a first end 221 e of the feed stalk 221 of low bandradiating element 220-1 can be positioned laterally outward of theoutermost radiating element of the antenna assembly 1195 of the activeantenna module 110 (e.g., a massive MIMO array) and can reside at aright side or a left side of the reflector 170. A feed circuit 315 onthe feed stalk 221 comprises RF transmission lines that are used to passRF signals between the dipole arms of the cross-dipole radiatingelements and a feed network of a base station antenna 100. The feedstalk 221 may also be used to mount the dipole arms at an appropriatedistance in front of the reflector 170 of base station antenna 100,which is often approximately 3/16 to ¼ of an operating wavelength. The“operating wavelength” refers to the wavelength corresponding to thecenter frequency of the operating frequency band of the radiatingelement 220. The radiating elements 220 can be dipole elementsconfigured to operate in some or all the 617-960 MHz frequency band. Thefeed circuit 315 typically comprises a hook balun provided on the feedstalk 221. Further discussions of example antenna elements includingantenna elements comprising feed stalks can be found in co-pending U.S.Provisional Patent Application Ser. Nos. 63/087,451 and 62/993,925, thecontents of which are hereby incorporated by reference as if recited infull herein.

Turning now to FIGS. 29, 30A and 30B, a first embodiment of a fieldinstallation configuration is shown. The active antenna module 110 canbe simply inserted from the top 100 t of the housing and slides into thetop cap and middle cap regions as shown by arrow A. The active antennamodule 110 is a sealed unit comprising an array of antenna elements 1195and radio circuitry 1120 and with the radome 119 as discussed above.

Turning now to FIGS. 31A, 31B, 32A, 32B, 33A-33C, another installationconfiguration using a bottom support 313 in antenna housing 100 h can beused. As shown in FIG. 31B, this allows for the active antenna module110 to be assembled at various angles relative to the housing 100 hwhich may facilitate ease of field installation. The bottom 110 b of theactive antenna module 110 can engage the housing 100 h first, thenrotate inward at the desired longitudinal stop location or slidedownward to fully engage the lower stop location (indicated by arrows A,B, C). The adapter member 2900″ can be provided with a support feature2913 at the bottom, extending a distance under the bottom 110 b of theactive antenna module 110. The adapter member 2900″ can then be affixedto the housing 100 h using fixation members 411 which can be bolts 411 b(FIG. 32A) or latches 4111 (FIG. 32B) or other fixation devices. FIGS.31A, 33A illustrate a tab configuration of the support feature 2913,which can be provided on right and left sides or in a middle region atthe rear 100 r of the housing 100 h. FIG. 33B illustrates a channel withan open top and closed bottom (such as an extruded channel) that engagesthe support feature 2913. FIG. 33C illustrates a snap fit configurationof the support feature 2913 and bottom support 313″ provided by thehousing 100 h.

Turning to FIGS. 34, 35A, 35B, 35C, as discussed above, the bottomsupport structure can comprise a bolt 189 that engages a lower edge 2901of the adapter member 2900.

FIGS. 36 and 37A-37C illustrates a stop block 289 extending upward fromthe rail 180 instead of a laterally extending bolt 189 and the loweredge 2901′ of the adapter member 2900′ can comprise a planarconfiguration with a stepped perimeter that engages the stop sidewall289 s of the stop block 289 while the planar lower edge 2901′ extendsinto the stop block 289. The stop block 289 can comprise a polymer toavoid metal to metal contact.

FIGS. 38 and 39A-39C illustrate another embodiment of the stop block 289which does not require the side stop wall shown above. The stop block289 can be fixed via a fixation member 289 f such as a bolt or threadedscrew the first surface 182 of the rail 180 to position the rear surface289 r of the stop block 289 to be flush with the first surface 182 ofthe rail 180.

FIGS. 40A and 40B illustrate the rail frame 180 f which is configured toprovide support and sealing functionality (sealing to the intermediateradome or skin 1129) as discussed above. The passive reflector 170 canbe fixed to the frame 180 f using a fixation member 388 such as a rivet.The adapter 2900 can be fixed to the rail frame 180 f with a rivet nut288 to strengthen the rails 180 when certain materials having lightweight (e.g., aluminum) are used.

FIGS. 41A and 41B illustrates fixed and adjustable tilt configurations,respectively, of the base station antenna 100 with associated mountinghardware. In these embodiments, there can be four attachment locationsbetween the base station antenna 100 and three or four attachments tothe mounting structure 300, such as a pole as shown. For the adjustabletilt configuration shown in FIG. 41B, a tilt rod fixture 311 can beused. FIG. 41C illustrates an adjustable tilt configuration using threedirect attachment points provided by mounting hardware/brackets 310between the base station antenna 100 and mounting structure 300 withoutrequiring the tilt rod fixture 311. The base station antenna andmounting structure 300 components can be mechanically attached allowingfor only three longitudinally spaced apart mount brackets 310 and a fulltilt range while reducing weight of the mounting hardware by 20% or moreover the configuration shown in FIG. 41B and 8% over the fixed tiltconfiguration shown in FIG. 41A.

FIGS. 41D and 41E illustrate sets 310 s of three pieces of mountinghardware 310 configured for providing 0-10 degree tilt (FIG. 41D) and a0-5 degree tilt (FIG. 41E) mounting orientation of the base stationantenna 100. Only one mounting bracket 310 of the set of the mountinghardware 310 s is required to be affixed to the active antenna unit 110as shown in FIG. 41C.

Turning now to FIGS. 42, 43, 44A-44C, 45A and 45B, the adapter 2900′″ ofthe active antenna module 110 can be configured to first couple to a topsupport feature 1311 allowing the active antenna module 110 to be placedat a number of angles relative to the housing 100 h, then slid down tocouple to the top support feature (arrow A), then rotated inward (arrowB), then optionally slid further down a distance (arrow C). Fixationmembers 411 can then be used to attach the active antenna module 110 tothe housing 100 h. The top support feature 1311 can provided as a hookchannel 1311 that captures a hook 2923 of the adapter member 2900′″(FIG. 44A), an extruded channel 1312 that receives a segment 2924 of theadapter member 2900′″ or even a longitudinally extending bolt channel2925 with a bolt opening at one end sized to receive the head of thebolt 1313 that merges into a narrower segment. The bolt channel is shownas provided in the adapter member 2900′″ but the reverse configurationcan be used with the bolt channel 2925 can be provided in the housing100 h and the bolt 1313 in the adapter 2900′″. Again, the fixationmembers 411 can be bolts 411 b or latches 4111 or other members.

Turning now to FIGS. 46A-46C, a portion of a base station antenna 100with a passive antenna reflector 170 and radiating elements 222 insidean external radome defined by a front 100 f of the base station antennahousing 100 h according to some embodiments of the present invention isshown. As discussed above, the radiating elements 222 can be low bandradiating elements provided in a plurality of linear arrays (columns)220-1, 220-2. FIG. 46B illustrates the passive antenna reflector 170 canbe provided as a frequency selective surface and/or substrate (“FSS”)170 f comprising an FSS material 1500. FIG. 46C shows the reflector 170provided as a metal reflector.

FIG. 47A is a graph of the azimuth pattern for an antenna beam generatedby one of the lower-band linear arrays included in the base stationantenna of FIG. 46B, as generated by a computational model. Thereflector 170 f illustrated comprises a dielectric constant of 3.7.However, it is contemplated that materials with lesser or greaterdielectric constants can be used. FIG. 47B is a graph of the azimuthpattern for the antenna beam based on a metal reflector (PEC refers toperfect electric conductor, e.g., the ideal case for a conductor) asshown in FIG. 46C, as generated by a computational model. FIGS. 47C,47D, 48A and 48B are additional graphs comparing the low bandperformance of the configurations of FIGS. 46B and 46C. Thecomputational model(s) show that low band performance of bothconfigurations is substantially similar.

FIG. 49A and FIG. 49B illustrate a portion of a base station antenna 100with the passive antenna reflector 170 provided as a frequency selectivesurface and/or substrate (“FSS”) 170 f with the FSS material 1500according to embodiments of the present invention.

FIG. 50A and FIG. 50B illustrate a portion of the base station antenna100 with two internal radomes 119, 1129, residing between an activeantenna reflector 1172 of the active antenna module 110 comprising radiocircuitry 1120 and the external radome defined by the front 100 f of thebase station antenna 100 according to embodiments of the presentinvention. The active antenna reflector 1172 can be (capacitively)coupled to a metal passive antenna reflector 170.

FIGS. 51, 52A-52D, 53A and 53B are graphs generated by a computationalmodel(s) comparing (low band) performance of the devices shown in FIGS.49A and 50A. The front-to-back ratio for the antenna with the FSSreflector 170 f is about 17.4 dB verses a front-to-back ratio of 13.45dB for the two intermediate radomes configuration with the activeantenna reflector 1172 coupled to the (metal) reflector 170.

Turning now to FIGS. 54A, 54B, 55A and 55B, a portion of a base stationantenna 100 with an active antenna module 110 and one or more (side)feed boards 1200 (FIG. 54B) that extend in a front to back direction ofthe base station antenna 100. The one or more feed boards 1200 are notrequired to be parallel with the passive antenna reflector 170 and canreside at an angle (e.g., between 90-120 degrees) from the primarysurface of the FSS material 1500, the passive antenna reflector 170, 214and/or the active antenna reflector 1172 according to embodiments of thepresent invention. As shown in FIGS. 54B and 54C, the feed boards 1200can extend perpendicular to the passive reflector 170 and/or FSSmaterial 1500.

In some embodiments, referring to FIGS. 54A, 54B, the FSS material 1500can extend laterally across an entire width W dimension of the front 100f of the housing 100 h and/or the external radome. In contrast to theembodiment shown in FIG. 22C, there is no front surface reflector spacefor the feed boards 1200 to be installed on. The extended width of theFSS material 1500 may minimize the possible effect of passive reflectorside segment edges 170 s on massive MIMO array 1195 performance, wheninstalled behind the FSS material 1500 and/or passive reflector 170 f.

The one or more feed board 1200 can be configured to be perpendicular toand reside adjacent to an outer perimeter portion of the passive antennareflector 170 and/or active antenna reflector 1172. The passivereflector side segments 170 s can have (metal or FSS) wall segments 1204that that are perpendicular to the primary surface of the FSS material1500 and the primary surface of the primary passive antenna reflector214 and can have an inwardly or outwardly extending dimension defining awidth “W” and a longitudinally extending dimension “L”. The passivereflector 170 can be provided as a laterally extending metal segment1202 that joins a longitudinally extending right side wall segment 1204and a longitudinally extending left side wall segment 1204 that extendabout a perimeter of the FSS material 1500.

Referring to FIGS. 54B, 54C, the feed boards 1200 can be coupled toand/or held in position by the wall segments 1204 of the (metal)reflector side segments 170 s and coupled to one or more feed stalks ofradiating antenna elements. The feed stalks may be feed stalks of lowand/or mid band elements such as radiating elements 222 and/or 232. Thefeed boards 1200 can be capacitively coupled to the side segments 170 sof the passive reflector 170. The feed boards 1200 can reside inside oroutside of the wall segments 1204.

The passive antenna reflector 170 can, but is not required to, comprisethe FSS 170 f with the FSS material 1500. Some or all of the low ormid-band radiating elements 222, 232, respectively, may be mounted onthe feed boards 1200 and can couple RF signals to and from theindividual radiating elements 222, 232. Cables (not shown) and/orconnectors may be used to connect each feed board to other components ofthe base station antenna 100 such as diplexers, phase shifters,calibration boards or the like.

FIGS. 56A and 56B are graphs of the azimuth pattern (scan angles of 0deg, 48 deg, respectively) for an antenna beam generated by one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B, as generated by a computational model with a top radomeremoved, 15 mm pushed back, and horizontal cut (in the orientation shownin FIG. 55A) at about 30 mm. FIG. 56C is a graph of return loss (dB)versus frequency (GHz) at 0 and 48 degree scan angles for an antennabeam generated by one of the lower-band linear arrays included in thebase station antenna of FIGS. 55A, 55B, as generated by a computationalmodel with a top radome removed, 15 mm pushed back, and horizontal cut(in the orientation shown in FIG. 55A) at about 30 mm. FIG. 56D is apolar active (RL) chart of 0 and 48 degree scan angles of one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B, as generated by a computational model with a top radomeremoved, 15 mm pushed back, and horizontal cut (in the orientation shownin FIG. 55A) at about 30 mm.

FIG. 56E is a graph of gain (dB) versus frequency (GHz) at 0 and 48degree scan angles of one of the lower-band linear arrays included inthe base station antenna of FIGS. 55A, 55B, as generated by acomputational model.

FIGS. 57A and 57B are graphs of the azimuth pattern (scan angles of 0deg, 48 deg, respectively) for an antenna beam generated by one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B and taken at a horizontal (in the orientation shown in FIG.55A) 60 mm cut position, as generated by a computational model. FIG. 57Cis a graph of return loss (dB) versus frequency (GHz) at 0 and 48 degreescan angles for an antenna beam generated by one of the lower-bandlinear arrays included in the base station antenna of FIGS. 55A, 55B,taken at the 60 mm cut position, as generated by a computational model.FIG. 57D is a polar active (RL) chart of 0 and 48 degree scan angles ofone of the lower-band linear arrays included in the base station antennaof FIGS. 55A, 55B taken at the 60 mm cut position from that of FIG. 56D,as generated by a computational model. FIG. 57E is a graph of gain (dB)versus frequency (GHz) at 0 and 48 degree scan angles of one of thelower-band linear arrays included in the base station antenna of FIGS.55A, 55B, taken at the 60 mm cut position from that of FIG. 56E, asgenerated by a computational model.

Turning now to FIGS. 58A, 58B, 59A and 59B, a portion of a base stationantenna with an active antenna module 110 and with a guide member 1300that releasably holds a FSS material 1500 that can form a reflector 170f is shown according to yet other embodiments of the present invention.The guide member 1300 can be slidably removed via the top 100 t (FIG.19A).

FIGS. 58A and 59A show the active antenna module 110 coupled to the basestation antenna 100 with the guide member 1300 held behind the front 100f of the base station antenna 100. The guide member 1300 can hold theFSS material 1500, optionally configured as a flexible substrate 1500 ssuch as a flex circuit 1500 f. The flexible substrate 1500 s can be laidon and/or pressed against a target surface and released from the guidemember 1300 to (conformably) attach to the target internal surface. Insome embodiments, the target internal surface can be the passiveintermediate radome 1129 that seals the rear 100 r of the housing 100 hof the passive antenna 100 or can be the radome 119 of the activeantenna module 110. The flexible substrate 1500 s can be attached to thepassive radome 1129 or the active antenna module radome 119 using theguide member 1300.

The guide member 1300 can be semi-rigid so as to be able to retain adefined three-dimensional shape in absence of an applied compressiveforce but can be compressed to push the flexible substrate 1500 sagainst the target surface, e.g., radome 1129 or radome 119, forexample. The flexible substrate 1500 s can be adhesively attached to thetarget internal surface, such as passive antenna intermediate radome1129 and/or active antenna module radome 119 and/or attached by otherattachment configurations such as, for example, rivets or hook and loop(VELCRO) arrangements.

In some embodiments, the guide member 1300 can be provided as theintermediate radome 1129 that is attached to the rear 100 r of thehousing and is not required to be removed. Thus, the guide member 1300can define both the intermediate radome 1129 and the reflector 170 f Theflexible substrate 1500 s can be attached to an internal facing primarysurface of the guide member 1300. The guide member 1300 can be malleableso as to have a first configuration with the primary surface closer to afront 100 f of the housing 100 h and a second configuration where theprimary surface resides further away from the front 100 f of thehousing. In the second configuration, the primary surface is adjacentto, optionally abutting the radome 119 of the active antenna module 110.

The intermediate radome 1129 can be positioned between the activeantenna reflector 1172 and the passive antenna reflector 170 f accordingto embodiments of the present invention.

Turning now to FIGS. 60A-60C, another embodiment of a base stationantenna housing 100 h is shown. In this embodiment, the base stationantenna housing 100 h includes a pair of longitudinally extending rails180 ₁, 180 ₂ that reside inside a rear wall 100 w of the housing,defining internal rails 180, laterally spaced apart across the cavity155. The base station antenna housing 100 h also includes a pair oflongitudinally extending external rails 1280 ₁, 1280 ₂. The externalrails 1280 ₁, 1280 ₂ are laterally spaced apart and reside on opposingsides of the cavity 155. The internal rails 180 ₁, 180 ₂ are coupled tocorresponding external rails 1280 ₁, 1280 ₂. The internal rails 180 canbe, and typically are, longer than the external rails 1280. The internalrails can provide structural rigidity for the housing 100 h.

The rear 100 r of the housing 100 h can be configured with a closedsurface of the rear wall 100 w extending over sides 101, 103 and thecavity 155, covering and parallel to the front 100 f. No seal cap 165(FIG. 5 ) is required. Rather, the rear wall 100 w of the housing 100 hcan be continuous from the top 100 t to bottom of the housing 100 h andbetween both side portions 101 b, 103 b.

The rear wall 100 w of the housing 100 h can have a rearward projectingshoulder 105 that extends between the internal rail 180 and the externalrail. The shoulder 105 can have a narrow width, typically between 5-20%of a width of the recess 155.

The closed surface of the wall 100 w at the rear 100 r of the housing100 h can define a “skin” and/or second inner facing radome 1129 thatextends between the radome 119 of the active antenna module 110 and thefront external radome 150, when the active antenna module 110 is inposition thereat.

A laterally and longitudinally extending primary portion of the rearwall 100 w can project further distances rearward at successivelongitudinally spaced apart segments, shown as a first segment 100 r 1adjacent the cavity 155, then to a second segment 100 r 2 that islongitudinally spaced apart from the first segment 100 r 1, then to athird segment 100 r 3. The second segment 100 r can be provided toaccommodate radio cable routing on longer radios, longer active antennamodules 110. The adapter member 2900, 2900′, such as an adapter frame,rails or plate, of the active antenna module 110 can reside over thecavity 155 and have a longitudinal extent that fits within the firstsegment 100 r 1 or the first and second segments 100 r 1, 100 r 2, forexample.

FIG. 61 illustrates that the depth or front to back dimension ofdifferent active antenna modules 110 can vary, but respective radomes119 of each can be configured to fit in the cavity 155. A respectiveadapter member 2900, 2900′ can be configured to accommodate differentactive antenna modules 110 or different radios 1120 thereof as shown inFIGS. 63A-63E. The adapter member 2900, 2900″, for example, can beconfigured to mount a respective radio 1120 with dimensions within about440 mm by 10000 mm (width times length), in some particular embodiments.

Turning now to FIGS. 62A and 62B, the base station housing 100 h can beprovided as a first housing member 100 h 1 defining a front 100 f of ahousing of the base station antenna 100 h and a second housing memberdefining a back 100 r of the base station antenna housing 100 h. Asshown, the first and second housing members 100 h 1, 100 h 2 extendlaterally and longitudinally and are sealed together alonglongitudinally extending side wall interfaces 100 i.

The first housing member 100 h 1 comprises a front surface 100 f thatmerges into right and left side portions, 101 a, 103, respectively, thatextend rearward. The second housing member 100 h 2 comprises a rear wall100 w that merges into right and left side portions 101 b, 103 b,respectively, that extend forward. The right and left side portions 101a, 103 a, of the first housing member 100 h 1 are coupled to the rightand left side portions 101 b, 103 b, of the second housing member 100 h2 along a joint interface 100 i that can extend longitudinally a lengthof the housing 100 h. The left and right side portions 101 a, 103 a ofthe first housing member 100 h can extend rearward a distance that isless than a shortest depth that the left and right side portions 101 b,103 b extend forward. The first housing member 100 h 1 and the secondhousing member 100 h 2 can be vacuum formed providing a lightweight butsufficiently rigid structure with relatively complex shapes.

The second housing member 100 h 2 provides at least one laterally andlongitudinally extending recess 155 (which can also be interchangeablydescribed as a cavity) adjacent a lower and/or upper end of the housing100 h. The recess 155 can extend along a sub-length of the housing 100h. The recess 155 can have a lateral extent that is 60-99% of a lateralextent of the housing 100 h.

The second housing member 100 h 2 comprises at least one externalstepped region 100 r 1 that rises above (projects rearward of) therecess 155 and extends laterally and longitudinally about anothersub-length of the housing 100 h.

Referring to FIG. 62C, the base station antenna 100 can include at leastone support member 1400 that resides between the first and secondhousing members 100 h 1, 100 h 2, typically residing adjacent a top 100t and/or bottom end portion 100 b of the housing 100 h.

The support member 1400 has a front 1400 f that faces the first housingmember 100 h 1 and a back 1400 b that faces an inner surface of thesecond housing member 100 h 2. The back 1400 b has a laterally extendingmedial segment 1400 m that is recessed relative to right and left sides1400 s of the support member 1400. The front 1400 f of the supportmember 1400 can have a shape that corresponds to a shape of the externalradome 150 and/or front 100 f of the housing 100 h. The right and leftsides 1400 s of the support member 1400 can extend between the right andleft sides 101 a, 101 b and 103 a, 103 b of the first and second housingmembers 100 h 1, 100 h 2.

FIG. 64A illustrates a base station antenna housing 100 h comprising twolongitudinally spaced apart cavities 155, each cavity 155 sized andconfigured to receive a corresponding one active antenna module 110(FIG. 64B). The housing 100 h includes two pairs of external rails 1280p ₁, 1280 p ₂, one pair residing on opposing lateral sides of the firstcavity 155 and the other pair residing on opposing lateral sides of theother cavity 155. As shown in FIG. 64B, each respective active antennamodule 110 can have an adapter member(s) 2900 that couples to theexternal rails 1280 ₁, 1280 ₂ at the corresponding cavity 155. Eachmodule 100 can have a different adapter member 2900 and each module 110can have a different radio configuration and/or body configurationrearward of and/or outside the housing 100 h.

FIGS. 65 and 66 illustrate a base station antenna housing 100 h with anexternal reflector 1450 extending about the cavity 155. The externalreflector 1450 can be coupled to, and extend external to, the rear wall100 w of the housing 100 h. Thus, the term “external” with respect to“external reflector” means that the reflector 1450 is exposed andexternally visible when an active antenna module 110 is not mounted onthe housing 100 h thereat. Typically, the external reflector 1450 iscoupled to the external rails 1280 ₁, 1280 ₂. The external reflector1450 can have a width and length that corresponds to the width andlength of the cavity 155 but may have a greater width and a greaterlength, e.g., about 10-20% greater, in some embodiments. As shown, theexternal reflector 1450 can have a primary forward surface 1450 f thatmerges into left and right sides 1451 that project rearward and extendlongitudinally and that merge into laterally extending lips 1453 thatcouple to the external rails 1280 ₁, 1280 ₂.

The reflector 1450 can comprise a metal surface and/or a frequencyselective surface as discussed.

In some embodiments, the external reflector 1450 can be removed beforethe active antenna module 110 is mounted in the corresponding cavity 155(FIG. 66 ).

FIG. 67A illustrates a conventional reflector comprising radiating(antenna) elements. FIG. 67B illustrates a reflector 170 of the basestation antenna comprising reflector sides 170 s in the shape ofelongate thin strips. The term “thin” with respect to strips of thereflector means 1-20% of an overall width of the base station antenna100.

Use of the external reflector 1450 can facilitate operation of theradiating elements 222 that extend in front of the reflector 170 s andthat also extend in front of the external reflector 1450 or aperture173, particularly when the active antenna module 110 with associatedreflector 1172 is not in position.

In some embodiments, as shown for example, in FIGS. 65 and 68A, theexternal reflector 1450 is detachably coupled to the housing 100 h, suchas to the external rails 1280 ₁, 1280 ₂, and is removed beforeinstalling a module 110 to the cavity 155 thereat.

In some embodiments, as shown for example in FIG. 68B, the externalreflector 1450 can remain in position when the active antenna module 110is coupled to the housing 100 h. This configuration can allow for(additional) radiating antenna elements 1222 to be positioned forward ofthe external reflector 1450. In this configuration, the externalreflector becomes a first internal reflector that is forward of thepassive antenna reflector 170/170 s, closest to the external radome 150,and also forward of the reflector 1129 of the active antenna module 110.

Referring to FIGS. 69, 70A, 70B, an external rail 1280 can be coupled tothe internal rail 180 of the base station antenna housing 100 h. Therear wall 100 w of the housing 100 h can have a rearward projectingshoulder 105 that extends between the internal rail 180 and the externalrail. The internal rail 180 can be sealably coupled to the external rail1280 to thereby inhibit water flow into the (radome) housing 100 h.

The internal rail 180 can be provided as a pair of laterally spacedapart rails 180 ₁, 180 ₂ that are covered by/reside inside theradome/housing 100 h and arranged on two longitudinal edges of thereflector 170 s to increase the stiffness thereof. The external rail1280 can also be provided as a pair 1280 p of external rails 1280 ₁,1280 ₂ that are laterally spaced apart. In some embodiments, theexternal rails 1280 ₁, 1280 ₂ are disposed outside the top portion ofthe housing 100 h at positions corresponding to those of the two longerinternal rails 180 ₁, 180 ₂ to support an active antenna 110. In someembodiments, the external rails 1280 ₁, 1280 ₂ are provided as two pairsof external rails, one coupled to a top portion of the housing 100 h andone coupled to a bottom portion of the housing (FIG. 64A).

At least one bolt 1286 can extend through an aligned bolt channel 185 ofan internal rail 180, an aperture 106 in the rear wall 100 w of thehousing 100 h and a bolt channel 1282 in an external rail 1280. A spacer1340 with a bolt hole 1343 can between the aligned bolt channels 1282,185. Typically, a first bolt 1286 is provided at one end portion of theexternal rail 1280 and a second bolt 1286 is provided at alongitudinally spaced apart opposing end portion.

The spacer 1340 can have a first portion 1341 that comprises the bolthole 1343 and a second portion 1342 of different material relative tothe first portion 1341 that surrounds the first portion 1341. The spacer1340 can provide increased contact surface area and can facilitateconsistent compression of the second portion 1342. The first portion1341 and the second portion 1342 can be elongate and can extend along alength dimension of the rails 180, 1280. The first portion 1341 can haveincreased rigidity relative to the second portion 1342. The secondportion 1342 can comprise rubber or other suitable seal material and maycomprise a resiliently compressible material. The first portion 1341 cancomprise metal such as aluminum or aluminum alloy, for example.

The first portion 1341 of the spacer 1340 can be defined as a metal ringand the second portion 1342 can be defined by a sealing pad surroundingthe metal ring. The first portion 1341 can be fixed in the center of thesecond portion 1342 by interference fit or other suitable attachmentconfigurations.

The second portion 1342 of the spacer 1340 can be configured to seal thegap between the short rail 180 and the rear wall 100 w of the housing100 h and can be compressed between these two components. The secondportion 1342 can comprise a plurality of discontinuous curved grooves1342 g. The first portion 1341 of the spacer 1340 can be configured tocontrol a compression height of the second portion 1342 so that thesecond portion 1342 is not over-compressed during assembly.

Before compression, a height of the second portion 1342 can be largerthan that of the first portion 1341 (FIG. 70B). After compression, atassembly, the second portion 1342 can be compressed by about 20-60%,typically about 40%, and thereby the compressed, installed, height ofthe second portion 1342 can be less than that of the first portion 1341,resulting in that the first portion 1341 partially sits into theaperture 106 of the rear wall 100 w/radome, and abuts the longerinternal rail 180 and the external rail 1280 with its opposing primarysurfaces, respectively, as shown in FIG. 74 . The aperture 106 can beconfigured to be large enough to adapt the positional tolerance of thecorresponding bolt holes 185, 1283 of the rails 180, 1280 in thelongitudinal direction of the housing 100 h.

As shown in FIGS. 70A, 70B, for example, the outer perimeter of thefirst portion 1341 can be oval, so as to adapt the narrow edge of theshoulder 105 of the rear wall 100 w in the transverse direction, and toincrease the structural strength in the longitudinal direction. Theouter perimeter of the second portion 1342 of the spacer 1340 can alsobe oval and can ride behind the aperture 106 of the shoulder 105 of therear wall 100 w of the housing 100 h.

Thus, the first portion 1341 of the spacer 1340 can reside in theaperture 106 in the rear wall 100 w of the housing 100 h. The aperture106 can have a shape that corresponds to the first portion 1341 of thespacer 1340. The bolt 1286 extends through the bolt channel 1282 in theexternal rail 1280, then through the bolt hole 1343 of the spacer 1340,then into the bolt channel 185 of the internal rail 180. The secondportion 1342 of the spacer 1340, 1340′ can abut, and be compressedbetween, an inner facing surface 1280 i of the external rail 1280 and arear facing surface 105 r of the shoulder 105 as shown in FIG. 74 .

FIGS. 71A, 71B illustrate another embodiment of a spacer 1340′ with twobolt holes 1343 and correspondingly shaped apertures 106 in the shoulder105 of the rear wall 100 w of the housing 100 h. The spacer 1340′ hastwo circular or ring shaped first portions 1341 and one elongate secondportion 1342 that surrounds both bolt holes 1343. Use of two or morecircular first portions 1341, spaced longitudinally apart, can dispersethe compression force felt by a single circular one.

As discussed with respect to the spacer of FIG. 70A, the second portion1342 of the spacer 1340, 1340′ can comprise a resilient compressiblematerial and can reside against an outer surface of the rear wall 100 wof the housing 100 y with the first, more rigid, e.g., metal, portion1341 of the spacer, 1340, 1340′ in a respective and correspondinglyshaped hole 106 in the rear wall 100 w/shoulder 105 of the housing 100h.

Referring now to FIGS. 72A-72C, the external rail 1280 can be sealedfrom the housing 105 at an interface behind the spacer 1340. As shown,the bolt channel 1282 of the external rail 1280 can comprise a groove1285 that surrounds a bolt aperture 1283. A seal member 1288 such as anO-ring or gasket can be held in the groove 1285. The bolt head 1286 or abolt collar 1286 c extending forward of the head 1286 h can beconfigured to reside against the seal member 1288 with the bolt bodyextending forward thereof. The groove 1285 can surround the bolt hole1283 with a resilient seal member 1288 in the groove 1285. The bolt 1286extends through the bolt hole 1283 with the head 1286 h of the bolt 1286and/or a collar 1286 c extending forward of the head 1286 h configuredto compress the resilient seal member 1288 thereby sealing the externalrail 1280 from the shoulder 105 of the rear wall 100 w of the housing100 h.

FIG. 73 illustrates another embodiment of a bolt 1286′ with anintegrated or coupled seal member 1288′ that does not require the groove1288 shown in FIGS. 72A-72C. The seal member 1288′ can be provided as anO-ring that is in front of the head 1286 h and collar 1286 c (in theassembled orientation). The collar 1286 c can slope in a directiontoward the shoulder 105 of the rear wall 100 w of the housing 100 h sothat the O-ring 1288′ can be housed within the sloping collar 1286 cafter assembly.

FIG. 74 shows the bolt 1286, 1286′ in the bolt channel 1282 of theexternal rail 1280 with the seal member 1288, 1288′ compressed against asurface of the external rail behind the spacer 1340, 1340′ with thesecond portion 1342 of the spacer 1340, 1340′ compressed between theinner facing surface 1280 i of the external rail 1280 and the outersurface 15 r of the shoulder 105 of the housing 100 h. The first portion1341 of the spacer 1340, 1340′ can about the inner facing surface 1280 iof the external rail 1280 and a rear facing surface 181 of the internalrail 180.

Embodiments of the present invention have been described above withreference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likenumbers refer to like elements throughout.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms. These terms are only used to distinguish oneelement from another. For example, a first element could be termed asecond element, and, similarly, a second element could be termed a firstelement, without departing from the scope of the present invention. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed items.

It will be understood that when an element is referred to as being “on”another element, it can be directly on the other element or interveningelements may also be present. In contrast, when an element is referredto as being “directly on” another element, there are no interveningelements present. It will also be understood that when an element isreferred to as being “connected” or “coupled” to another element, it canbe directly connected or coupled to the other element or interveningelements may be present. In contrast, when an element is referred to asbeing “directly connected” or “directly coupled” to another element,there are no intervening elements present. Other words used to describethe relationship between elements should be interpreted in a likefashion (i.e., “between” versus “directly between”, “adjacent” versus“directly adjacent”, etc.)

Relative terms such as “below” or “above” or “upper” or “lower” or“horizontal” or “vertical” may be used herein to describe a relationshipof one element, layer or region to another element, layer or region asillustrated in the figures. It will be understood that these terms areintended to encompass different orientations of the device in additionto the orientation depicted in the figures.

The term “about” used with respect to a number refers to a variation of+/−10%.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”“comprising,” “includes” and/or “including” when used herein, specifythe presence of stated features, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, operations, elements, components, and/or groups thereof.

Aspects and elements of all of the embodiments disclosed above can becombined in any way and/or combination with aspects or elements of otherembodiments to provide a plurality of additional embodiments.

That which is claimed is:
 1. A base station antenna, comprising: a basestation antenna housing comprising a top, a bottom, a front, a rear andright and left side walls extending between the top and the bottom andjoining the front and rear, wherein the rear comprises a recessedsegment that extends longitudinally and laterally across the rear of thebase station antenna housing; a passive antenna assembly in the basestation antenna housing; and an active antenna module that includesradio circuitry and a plurality of radiating elements, wherein theactive antenna module resides behind and at least partially over therecessed segment of the rear of the base station antenna housing.
 2. Thebase station antenna of claim 1, wherein the front and the right andleft side walls comprise at least part of a radome, and wherein theactive antenna module is sealably coupled to the rear of the basestation antenna housing.
 3. The base station antenna of claim 1, whereinthe base station antenna housing comprises a bracket that is configuredto attach to a mounting structure, and wherein the active antenna moduleis slidably positionable to reside over the recessed segment while thebracket is attached to the mounting structure.
 4. The base stationantenna of claim 1, wherein the active antenna module comprises at leastone bracket that projects rearwardly.
 5. The base station antenna ofclaim 1, further comprising a back plate in the base station antennahousing with an open aperture, wherein the open aperture extendslongitudinally and laterally across the rear of the base station antennahousing, and wherein the active antenna module covers the open apertureof the back plate.
 6. The base station antenna of claim 1, wherein theactive antenna module and/or a back plate and/or first and secondlongitudinally extending rails in the base station antenna housingcomprise a seal configured to sealably couple the active antenna moduleto the base station antenna housing.
 7. The base station antenna ofclaim 1, wherein the right and left side walls have a first height alongthe recessed segment, wherein the right and left side walls have asecond height that is greater than the first height at a second segmentlongitudinally spaced apart from the recessed segment, and wherein adifference between the first and second heights is in a range of about0.25 inches and about 6 inches.
 8. The base station antenna of claim 1,wherein the recessed segment extends a length that is in a range ofabout 20%-60% of a length of the rear of the base station antennahousing and extends in a width direction, perpendicular to the lengthdirection, that is in a range of about 30-110% of a width of the rear ofthe base station antenna housing.
 9. The base station antenna of claim1, further comprising a seal cap sealably coupled to the left and rightside walls and the rear of the base station antenna housing at alocation that is adjacent a bottom of the recessed segment.
 10. The basestation antenna of claim 1, further comprising a reflector in the basestation antenna housing, wherein at least a portion of the reflectorresides forwardly of a back plate in the base station antenna housing.11. The base station antenna of claim 10, wherein the reflectorcomprises an open aperture that, with the base station antenna inoperative position, resides forward of the open aperture of the backplate.
 12. The base station antenna of claim 1, wherein the recessedsegment resides adjacent the top of the base station antenna housing andterminates above a medial segment of the rear of the base stationantenna housing.
 13. The base station antenna of claim 2, wherein theback plate is rectangular and has a rectangular perimeter that surroundsthe open aperture and that is sealably coupled to the active antennamodule.
 14. The base station antenna of claim 2, further comprisingfirst and second rails that are laterally spaced and that longitudinallyextend inside the base station antenna, wherein the first and secondrails are coupled to the base station antenna housing.
 15. The basestation antenna of claim 14, further comprising first and secondcross-members coupled to the first and second rails that togethersurround a window configured to receive the active antenna module. 16.The base station antenna of claim 14, wherein the first and second railsare sealably coupled to the active antenna module.
 17. The base stationantenna of claim 14, wherein the first and second rails are coupled to areflector in the base station antenna housing, optionally wherein thereflector is positioned a distance in a range of about 0.5 inches toabout 4 inches from a back plate in a front to back direction betweenthe front and rear of the base station antenna housing, and/oroptionally wherein the passive antenna assembly comprises feed boards onright and left sides of the base station antenna that are perpendicularto the reflector of the active antenna module.
 18. The base stationantenna of claim 1, further comprising a first reflector comprising afrequency selective surface and/or substrate that is configured toreflect RF energy at a low band and pass RF energy at a higher band. 19.The base station antenna of claim 1, further comprising a bolt thatextends through a first one of at least one internal rail in the basestation antenna housing, a rear wall of the base station antenna housingand a first one of at least one external rail attached to the basestation antenna housing.
 20. The base station antenna of claim 19,further comprising a spacer with a first portion comprising a bolt holesurrounded by a second portion of a different material, wherein thefirst portion of the spacer resides in a hole in the rear wall of thebase station antenna housing that has an opening with a shape thatcorresponds to the first portion of the spacer, and wherein the boltextends through the external rail, through the bolt hole of the spacerand into the internal rail.
 21. A base station antenna, comprising: abase station antenna housing comprising a top, a bottom, a front, a rearand right and left sides joining the front and rear, wherein the rearcomprises a longitudinally and laterally extending recessed segment; apassive antenna assembly in the base station antenna housing; and anactive antenna module sealably coupled to the rear of the base stationhousing over the recessed segment.
 22. The base station antenna of claim21, wherein the active antenna module comprises radio circuitry and aplurality of radiating elements.
 23. The base station antenna of claim21, further comprising a back plate with an open aperture, wherein theopen aperture extends longitudinally and laterally over the openchamber.
 24. The base station antenna of claim 23, wherein the activeantenna module and/or the back plate comprises a seal extending about aperimeter portion thereof.
 25. The base station antenna of claim 21,wherein the right and left side walls have a first height along therecessed segment of the rear, wherein the right and left side walls havea second height that is greater than the first height at a secondsegment of the rear that is longitudinally spaced apart from therecessed segment, and wherein a difference between the first and secondheights is in a range of about 0.25 inches and about 6 inches.
 26. Thebase station antenna of claim 25, wherein the recessed segment extends alength that is in a range of about 20%-60% of a length of the rear ofthe base station antenna housing and extends in a width direction,perpendicular to the length direction, that is in a range of about30-110% of a width of the rear of the base station antenna housing. 27.The base station antenna of claim 21, further comprising a seal capsealably coupled to the left and right side walls and the rear of thebase station antenna housing.
 28. The base station antenna of claim 23,further comprising a reflector in the base station antenna housing,wherein at least a portion of the reflector resides forwardly of theback plate.
 29. The base station antenna of claim 21, wherein therecessed segment resides adjacent the top of the base station antennahousing and terminates above a medial segment of the rear of the basestation antenna housing.
 30. A method of assembling a base stationantenna, comprising: mounting a base station antenna housing to amounting structure; aligning an active antenna module with a recessedrear segment and/or open chamber along a rear of the base stationantenna housing before or after mounting the base station antennahousing; then attaching the active antenna module against the mountedbase station antenna housing to thereby position the active antennamodule relative to the base station antenna housing.